SEXTUS EMPIRICUS AND GREEK SCEPTICISM
A Thesis accepted for the Degree of Doctor of Philosophy in the University of Bern Switzerland, November 1897
MARY MILLS PATRICK
PRESIDENT OF THE AMERICAN COLLEGE, CONSTANTINOPLE TURKEY
This Thesis is accompanied by a Translation from the Greek of the First Book of the "Pyrrhonic Sketches" by Sextus Empiricus
DEIGHTON BELL & CO.
LONDON GEORGE BELL & SONS
PRINTED BY JONATHAN PALMER
The following treatise on Sextus Empiricus and Greek Scepticism has been prepared to supply a need much felt in the English language by students of Greek philosophy. For while other schools of Greek philosophy have been exhaustively and critically discussed by English scholars, there are few sources of information available to the student who wishes to make himself familiar with the teachings of Pyrrhonism. The aim has been, accordingly, to give a concise presentation of Pyrrhonism in relation to its historical development and the Scepticism of the Academy, with critical references to the French and German works existing on the subject. The time and manner of the connection of Sextus Empiricus with the Pyrrhonean School has also been discussed.
As the First Book of the Hypotyposes, or Pyrrhonic Sketches by Sextus Empiricus, contains the substance of the teachings of Pyrrhonism, it has been hoped that a translation of it into English might prove a useful contribution to the literature on Pyrrhonism, and this translation has been added to the critical part of the work.
In making this translation, and in the general study of the works of Sextus, the Greek text of Immanuel Bekker, Berlin, 1842, has been used, with frequent consultation of the text of J.A. Fabricius, 1718, which was taken directly from the existing manuscripts of the works of Sextus. The divisions into chapters, with the headings of the chapters in the translation, is the same as Fabricius gives from the manuscripts, although not used by Bekker, and the numbers of the paragraphs are the same as those given by both Fabricius and Bekker. References to Diogenes Laertius and other ancient works have been carefully verified.
The principal modern authors consulted are the following:
Ritter, Geschichte der Philosophie, II. Auf., Hamburg, 1836-38.
Zeller, Philosophie der Griechen, III. Auf., Leipzig, 1879-89.
Lewes, History of Philosophy, Vol. I., London, 1866.
Ueberweg, History of Philosophy, IV. ed., translated by Morris, 1871.
Brochard, Les Sceptiques Grecs, Paris, 1877.
Brochard, Pyrrhon et le Scepticism Primitive, No. 5, Ribot's Revue Phil., Paris, 1885.
Saisset, Le Scepticism Aenesideme-Pascal-Kant, Paris, 1867.
Chaignet, Histoire de la Psychologie des Grecs, Paris, 1887-90.
Haas, Leben des Sextus Empiricus, Burghausen, 1882.
Natorp, Forschungen zur Geschichte des Erkenntnisproblems bei den Alten, Berlin, 1884.
Hirzel, Untersuchungen zu Cicero's philosophischen Schriften, Leipzig, 1877-83.
Pappenheim, Erlaeuterung zu des Sextus Empiricus Pyrrhoneischen Grundzuegen, Heidelberg, 1882.
Pappenheim, Die Tropen der Greichischen Skeptiker, Berlin, 1885.
Pappenheim, Lebensverhaeltnisse des Sextus Empiricus, Berlin, 1887.
Pappenheim, Der angebliche Heraclitismus des Skeptikers Ainesidemos, Berlin, 1887.
Pappenheim, Der Sitz der Schule der Griechischen Skeptiker, Archiv fuer Geschichte der Philosophie, I. 1, S. 47, 1887.
Maccoll, The Greek Sceptics from Pyrrho to Sextus, London, 1869.
My grateful acknowledgments are due to Dr. Ludwig Stein, Professor of Philosophy in the University of Bern, for valuable assistance in relation to the plan of the work and advice in regard to the best authorities to be consulted. Thanks are also due to Dr. Louisos Iliou, of Robert College, Constantinople, for kind suggestions concerning the translation.
THE HISTORICAL RELATIONS OF SEXTUS EMPIRICUS ... 1
Introductory paragraph.—The name of Sextus Empiricus. His profession.—The time when he lived.—The place of his birth.—The seat of the Sceptical School while Sextus was at its head.—The character of the writings of Sextus Empiricus.
THE POSITION AND AIM OF PYRRHONIC SCEPTICISM ... 23
The subject-matter of the Hypotyposes.—The origin of Pyrrhonism.—The nomenclature of Pyrrhonism.—Its criterion.—Its aim.—[Greek: epoche] and [Greek: ataraxia].—The standpoint of Pyrrhonism.
THE SCEPTICAL TROPES ... 31
Origin of the name.—The ten Tropes of [Greek: epoche].—The First Trope.—The Second Trope.—The Third Trope.—The Fourth Trope.—The Fifth Trope.—The Sixth Trope.—The Seventh Trope.—The Eighth Trope.—The Ninth Trope.—The Tenth Trope.—The five Tropes of Agrippa.—The two Tropes.—The Tropes of Aenesidemus against Aetiology.
AENESIDEMUS AND THE PHILOSOPHY OF HERACLITUS ... 63
Statement of the problem.—The theory of Pappenheim.—The theory of Brochard.—Zeller's theory.—The theory of Ritter and Saisset.—The theory of Hirzel and Natorp.—Critical examination of the subject.
CRITICAL EXAMINATION OF PYRRHONISM ... 81
Pyrrhonism and Pyrrho.—Pyrrhonism and the Academy. Strength and weakness of Pyrrhonism.
* * * * *
THE FIRST BOOK OF THE PYRRHONIC SKETCHES BY SEXTUS EMPIRICUS, TRANSLATED FROM THE GREEK ... 101
The Historical Relations of Sextus Empiricus.
Interest has revived in the works of Sextus Empiricus in recent times, especially, one may say, since the date of Herbart. There is much in the writings of Sextus that finds a parallel in the methods of modern philosophy. There is a common starting-point in the study of the power and limitations of human thought. There is a common desire to investigate the phenomena of sense-perception, and the genetic relations of man to the lower animals, and a common interest in the theory of human knowledge.
While, however, some of the pages of Sextus' works would form a possible introduction to certain lines of modern philosophical thought, we cannot carry the analogy farther, for Pyrrhonism as a whole lacked the essential element of all philosophical progress, which is a belief in the possibility of finding and establishing the truth in the subjects investigated.
Before beginning a critical study of the writings of Sextus Empiricus, and the light which they throw on the development of Greek Scepticism, it is necessary to make ourselves somewhat familiar with the environment in which he lived and wrote. We shall thus be able to comprehend more fully the standpoint from which he regarded philosophical questions.
Let us accordingly attempt to give some details of his life, including his profession, the time when he lived, the place of his birth, the country in which he taught, and the general aim and character of his works. Here, however, we encounter great difficulties, for although we possess most of the writings of Sextus well preserved, the evidence which they provide on the points mentioned is very slight. He does not give us biographical details in regard to himself, nor does he refer to his contemporaries in a way to afford any exact knowledge of them. His name even furnishes us with a problem impossible of solution. He is called [Greek: Sextos ho empeirikos] by Diogenes Laertius: [Greek: Herodotou de diekouse Sextos ho empeirikos hou kai ta deka ton skeptikon kai alla kallista' Sextou de diekouse Satorninos ho Kythenas, empeirikos kai autos]. Although in this passage Diogenes speaks of Sextus the second time without the surname, we cannot understand the meaning otherwise than that Diogenes considered Sextus a physician of the Empirical School. Other evidence also is not wanting that Sextus bore this surname. Fabricius, in his edition of the works of Sextus, quotes from the Tabella de Sectis Medicorum of Lambecius the statement that Sextus was called Empiricus because of his position in medicine.
Pseudo-Galen also refers to him as one of the directors of the Empirical School, and calls him [Greek: Sextos ho empeirikos]. His name is often found in the manuscripts written with the surname, as for example at the end of Logic II. In other places it is found written without the surname, as Fabricius testifies, where Sextus is mentioned as a Sceptic in connection with Pyrrho.
 Diog. Laert. IX. 12, 116.
 Fabricius Testimonia, p. 2.
 Pseudo-Galen Isag. 4; Fabricius Testimonia, p. 2.
 Bekker Math. VIII. 481.
The Sceptical School was long closely connected with the Empirical School of medicine, and the later Pyrrhoneans, when they were physicians, as was often the case, belonged for the most part to this school. Menedotus of Nicomedia is the first Sceptic, however, who is formally spoken of as an Empirical physician, and his contemporary Theodas of Laodicea was also an Empirical physician. The date of Menedotus and Theodas is difficult to fix, but Brochard and Hass agree that it was about 150 A.D. After the time of these two physicians, who were also each in turn at the head of the Sceptical School, there seems to have been a definite alliance between Pyrrhonism and Empiricism in medicine, and we have every reason to believe that this alliance existed until the time of Sextus.
 Diog. IX. 12, 115.
 Brochard Op. cit. Livre IV. p. 311.
 Diog. IX. 12, 116.
The difficulty in regard to the name arises from Sextus' own testimony. In the first book of the Hypotyposes he takes strong ground against the identity of Pyrrhonism and Empiricism in medicine. Although he introduces his objections with the admission that "some say that they are the same," in recognition of the close union that had existed between them, he goes on to say that "Empiricism is neither Scepticism itself, nor would it suit the Sceptic to take that sect upon himself", for the reason that Empiricism maintains dogmatically the impossibility of knowledge, but he would prefer to belong to the Methodical School, which was the only medical school worthy of the Sceptic. "For this alone of all the medical sects, does not proceed rashly it seems to me, in regard to unknown things, and does not presume to say whether they are comprehensible or not, but it is guided by phenomena. It will thus be seen that the Methodical School of medicine has a certain relationship to Scepticism which is closer than that of the other medical sects."
 Hyp. I. 236.
 Hyp. I. 237.
 Hyp. I. 241.
We know from the testimony of Sextus himself that he was a physician. In one case he uses the first person for himself as a physician, and in another he speaks of Asclepius as "the founder of our science," and all his illustrations show a breadth and variety of medical knowledge that only a physician could possess. He published a medical work which he refers to once as [Greek: iatrika hupomnemata], and again as [Greek: empeirika hupomnemata] These passages probably refer to the same work, which, unfortunately for the solution of the difficult question that we have in hand, is lost, and nothing is known of its contents.
In apparent contradiction to his statement in Hypotyposes I., that Scepticism and Empiricism are opposed to each other, in that Empiricism denies the possibility of knowledge, and Scepticism makes no dogmatic statements of any kind, Sextus classes the Sceptics and Empiricists together in another instance, as regarding knowledge as impossible [Greek: all oi men phasin auta me katalambanesthai, hoster hoi apo tes empeirias iatroi kai hoi apo tes skepseos phiolosophoi]. In another case, on the contrary, he contrasts the Sceptics sharply with the Empiricists in regard to the [Greek: apodeixeis]. [Greek: hoi de empeirikoi anairousin, hoi de skeptikoi en epoche tauten ephylaxan].
 Hyp. ii. 238.
 Adv. Math. A. 260.
 Adv. Math. vii. 202.
 Adv. Math. A. 61.
 Zeller Op. cit.. iii. 43.
 Adv. Math. viii. 191.
 Adv. Math. VIII. 328.
Pappenheim thinks that Sextus belonged to the Methodical School, both from his strong expression in favor of that school in Hyp. I. 236, as above, and also because many of his medical opinions, as found in his works, agree with the teachings of the Methodical School, more nearly than with those of the Empiricists. Pappenheim also claims that we find no inconsistency with this view in the passage given where Sextus classes the Sceptics with the Empiricists, but considers that statement an instance of carelessness in expressing himself, on the part of Sextus.
 Lebensverhaeltnisse des Sex. Em. 36.
The position of Pappenheim is assailable for the reason that in dealing with any problem regarding an author on the basis of internal evidence, we have no right to consider one of his statements worthy of weight, and another one unworthy, on the supposition that he expressed himself carelessly in the second instance. Rather must we attempt to find his true standpoint by fairly meeting all the difficulties offered in apparently conflicting passages. This has been attempted by Zeller, Brochard, Natorp and others, with the general result that all things considered they think without doubt that Sextus belonged to the Empirical School. His other references are too strong to allow his fidelity to it to be doubted. He is called one of the leaders of Empiricism by Pseudo-Galen, and his only medical work bore the title [Greek: empeirika hupomnemata.] The opinion of the writers above referred to is that the passage which we have quoted from the Hypotyposes does not necessarily mean that Sextus was not an Empiricist, but as he was more of a Sceptic than a physician, he gave preference to those doctrines that were most consistent with Scepticism, and accordingly claimed that it was not absolutely necessary that a Sceptic physician should be an Empiricist. Natorp considers that the different standpoint from which Sextus judges the Empirical and Methodical Schools in his different works is accounted for on the supposition that he was an Empiricist, but disagreed with that school on the one point only. Natorp points out that Sextus does not speak more favourably of the medical stand of the Methodical School, but only compares the way in which both schools regarded the question of the possibility of knowledge, and thinks that Sextus could have been an Empiricist as a physician notwithstanding his condemnation of the attitude of the Empirical School in relation to the theory of knowledge. This difference between the two schools was a small one, and on a subtle and unimportant point; in fact, a difference in philosophical theory, and not in medical practice.
 Brochard Op. cit. Livre IV. 317; Zeller Op. cit. III. 15; Natorp Op. cit. p. 155.
 Natorp Op. cit. 157.
While we would agree with the authors above referred to, that Sextus very probably recognized the bond between the Empirical School of medicine and Pyrrhonism, yet to make his possible connection with that school the explanation of his name, gives him more prominence as a physician than is consistent with what we know of his career. The long continued union of Empiricism and Scepticism would naturally support the view that Sextus was, at least during the earlier part of his life, a physician of that school, and yet it may be that he was not named Empiricus for that reason. There is one instance in ancient writings where Empiricus is known as a simple proper name. It may have been a proper name in Sextus' case, or there are many other ways in which it could have originated, as those who have studied the origin of names will readily grant, perhaps indeed, from the title of the above-named work, [Greek: empeirika hupomnemata.] The chief argument for this view of the case is that there were other leaders of the Sceptical School, for whom we can claim far greater influence as Empiricists than for Sextus, and for whom the surname Empiricus would have been more appropriate, if it was given in consequence of prominence in the Empirical School. Sextus is known to the world as a Sceptic, and not as a physician. He was classed in later times with Pyrrho, and his philosophical works survived, while his medical writings did not, but are chiefly known from his own mention of them. Moreover, the passage which we have quoted from the Hypotyposes is too strong to allow us easily to believe that Sextus remained all his life a member of the Empirical School. He could hardly have said, "Nor would it suit the Sceptic to take that sect upon himself," if he at the same time belonged to it. His other references to the Empirical School, of a more favorable character, can be easily explained on the ground of the long continued connection which had existed between the two schools. It is quite possible to suppose that Sextus was an Empiricist a part of his life, and afterwards found the Methodical School more to his liking, and such a change would not in any way have affected his stand as a physician.
 Pappenheim Leb. Ver. Sex. Em. 6.
In regard to the exact time when Sextus Empiricus lived, we gain very little knowledge from internal evidence, and outside sources of information are equally uncertain. Diogenes Laertius must have been a generation younger than Sextus, as he mentions the disciple of Sextus, Saturninus, as an Empirical physician. The time of Diogenes is usually estimated as the first half of the third century A.D., therefore Sextus cannot be brought forward later than the beginning of the century. Sextus, however, directs his writings entirely against the Dogmatics, by whom he distinctly states that he means the Stoics, and the influence of the Stoics began to decline in the beginning of the third century A.D. A fact often used as a help in fixing the date of Sextus is his mention of Basilides the Stoic, [Greek: alla kai oi stoikoi, os oi peri ton Basileiden]. This Basilides was supposed to be identical with one of the teachers of Marcus Aurelius. This is accepted by Zeller in the second edition of his History of Philosophy, but not in the third for the reason that Sextus, in all the work from which this reference is taken, i.e. Math. VII.-XI., mentions no one besides Aenesidemus, who lived later than the middle of the last century B.C. The Basilides referred to by Sextus may be one mentioned in a list of twenty Stoics, in a fragment of Diogenes Laertius, recently published in Berlin by Val Rose. Too much importance has, however, been given to the relation of the mention of Basilides the Stoic to the question of the date of Sextus. Even if the Basilides referred to by Sextus is granted to have been the teacher of Marcus Aurelius, it only serves to show that Sextus lived either at the same time with Marcus Aurelius or after him, which is a conclusion that we must in any case reach for other reasons.
 Diog. IX. 12, 116.
 Ueberweg Hist. of Phil. p. 21.
 Hyp. I. 65.
 Adv. Math. VII. 258.
 Fabricius Vita Sexti.
 Zeller Op. cit. III. 8.
 Brochard Op. cit. IV. 315.
The fact that has caused the greatest uncertainty in regard to the date of Sextus is that Claudius Galen in his works mentions several Sceptics who were also physicians of the Empirical School, and often speaks of Herodotus, supposed to be identical with the teacher of Sextus given by Diogenes Laertius, but makes no reference whatever to Sextus. As Galen's time passes the limit of the second century A.D., we must either infer that Sextus was not the well-known physician that he was stated to be by Pseudo-Galen, and consequently not known to Galen, or that Galen wrote before Sextus became prominent as a Sceptic. This silence on the part of Galen in regard to Sextus increases the doubt, caused by Sextus' own criticism of the Empirical School of medicine, as to his having been an Empiricist. The question is made more complicated, as it is difficult to fix the identity of the Herodotus so often referred to by Galen. As Galen died about 200 A.D. at the age of seventy, we should fix the date of Sextus early in the third century, and that of Diogenes perhaps a little later than the middle, were it not that early in the third century the Stoics began to decline in influence, and could hardly have excited the warmth of animosity displayed by Sextus. We must then suppose that Sextus wrote at the very latter part of the second century, and either that Galen did not know him, or that Galen's books were published before Sextus became prominent either as a physician or as a Sceptic. The fact that he may have been better known as the latter than as the former does not sufficiently account for Galen's silence, as other Sceptics are mentioned by him of less importance than Sextus, and the latter, even if not as great a physician as Pseudo-Galen asserts, was certainly both a Sceptic and a physician, and must have belonged to one of the two medical schools so thoroughly discussed by Galen—either the Empirical or the Methodical. Therefore, if Sextus were a contemporary of Galen, he was so far removed from the circle of Galen's acquaintances as to have made no impression upon him, either as a Sceptic or a physician, a supposition that is very improbable. We must then fix the date of Sextus late in the second century, and conclude that the climax of his public career was reached after Galen had finished those of his writings which are still extant.
 Zeller, III. 7.
 Diog. XI. 12, 116.
 Pappenheim Lebens. Ver. Sex. Em. 30.
 Zeller Grundriss der Ges. der Phil. p. 260.
Sextus has a Latin name, but he was a Greek; we know this from his own statement. We also know that he must have been a Greek from the beauty and facility of his style, and from his acquaintance with Greek dialects. The place of his birth can only, however, be conjectured, from arguments indirectly derived from his writings. His constant references throughout his works to the minute customs of different nations ought to give us a clue to the solution of this question, but strange to say they do not give us a decided one. Of these references a large number, however, relate to the customs of Libya, showing a minute knowledge in regard to the political and religious customs of this land that he displays in regard to no other country except Egypt. Fabricius thinks Libya was not his birth place because of a reference which he makes to it in the Hypotyposes—[Greek: Thrakon de kai Gaitoulon (Libyon de ethnos touto)]. This conclusion is, however, entirely unfounded, as the explanation of Sextus simply shows that the people whom he was then addressing were not familiar with the nations of Libya. Suidas speaks of two men called Sextus, one from Chaeronea and one from Libya, both of whom he calls Sceptics, and to one of whom he attributes Sextus' books. All authorities agree in asserting that great confusion exists in the works of Suidas; and Fabricius, Zeller, and Pappenheim place no weight upon this testimony of Suidas. Haas, however, contends that it is unreasonable to suppose that this confusion could go as far as to attribute the writings of Sextus Empiricus to Sextus of Chaeronea, and also make the latter a Sceptic, and he considers it far more reasonable to accept the testimony of Suidas, as it coincides so well with the internal evidence of Sextus' writings in regard to his native land. It is nevertheless evident, from his familiarity with the customs, language, and laws of Athens, Alexandria and Rome, that he must have resided at some time in each of these cities.
 Adv. Math. A. 246; Hyp. I. 152; Hyp. III. 211, 214.
 Haas Op. cit. p. 10.
 Hyp. III. 213.
 Pappenheim Lebens. Ver. Sex. Em. 5, 22; Zeller Op. cit. III. 39; Fabricius Vita de Sextus.
 Haas Op. cit. p. 6.
Of all the problems connected with the historical details of the life of Sextus, the one that is the most difficult of solution, and also the most important for our present purpose of making a critical study of his teaching, is to fix the seat of the Sceptical School during the time that he was in charge of it. The Hypotyposes are lectures delivered in public in that period of his life. Where then were they delivered? We know that the Sceptical School must have had a long continued existence as a definite philosophical movement, although some have contended otherwise. The fact of its existence as an organized direction of thought, is demonstrated by its formulated teachings, and the list given by Diogenes Laertius of its principal leaders, and by references from the writings of Sextus. In the first book of Hypotyposes he refers to Scepticism as a distinct system of philosophy, [Greek: kai taen diakrisin taes skepseos apo ton parakeimenon autae philosophion]. He speaks also of the older Sceptics, and the later Sceptics.
Pyrrho, the founder of the school, taught in Elis, his native village; but even as early as the time of Timon, his immediate follower, his teachings were somewhat known in Alexandria, where Timon for a while resided. The immediate disciples of Timon, as given by Diogenes, were not men known in Greece or mentioned in Greek writings. Then we have the well-known testimony of Aristocles the Peripatetic in regard to Aenesidemus, that he taught Pyrrhonism in Alexandria—[Greek: echthes kai proaen en Alexandreia tae kat' Aigypton Ainaesidaemos tis anazopyrein aerxato ton huthlon touton].
 Diog. XI. 12, 115, 116.
 Hyp. I. 5.
 Hyp. I. 36.
 Hyp. I. 164.
 Chaignet Op. cit. 45.
 Aristocles of Euseb. Praep. Ev. XIV. E. 446.
This was after the dogmatic tendency of the Academy under Antiochus and his followers had driven Pyrrhonism from the partial union with the Academy, which it had experienced after the breaking up of the school under the immediate successors of Timon. Aenesidemus taught about the time of our era in Alexandria, and established the school there anew; and his followers are spoken of in a way that presupposes their continuing in the same place. There is every reason to think that the connection of Sextus with Alexandria was an intimate one, not only because Alexandria had been for so long a time the seat of Pyrrhonism, but also from internal evidence from his writings and their subsequent historical influence; and yet the Hypotyposes could not have been delivered in Alexandria, as he often refers to that place in comparison with the place where he was then speaking. He says, furthermore, that he teaches in the same place where his master taught. [Greek: Blepon te hoti entha ho huphaegaetaes ho emos dielegeto, entautha ego nun dialegomai]. Therefore the school must have been removed from Alexandria, in or before the time of the teacher of Sextus, to some other centre. The Hypotyposes are from beginning to end a direct attack on the Dogmatics; therefore Sextus must have taught either in some city where the dogmatic philosophy was strong, or in some rival philosophical centre. The Hypotyposes show also that the writer had access to some large library. Alexandria, Rome and Athens are the three places the most probable for selection for such a purpose. For whatever reason the seat of the school was removed from Alexandria by the master of Sextus, or by himself, from the place where it had so long been united with the Empirical School of medicine, Athens would seem the most suitable city for its recontinuance, in the land where Pyrrhonism first had its birth. Sextus, however, in one instance, in referring to things invisible because of their outward relations, says in illustration, "as the city of Athens is invisible to us at present." In other places also he contrasts the Athenians with the people whom he is addressing, equally with the Alexandrians, thus putting Athens as well as Alexandria out of the question.
 Hyp. III. 120.
 Hyp. II. 98.
Of the different writers on Sextus Empiricus, those who have treated this part of the subject most critically are Haas and Pappenheim. We will therefore consider, somewhat at length, the results presented by these two authors. Haas thinks that the Hypotyposes were delivered in Rome for the following reasons. Sextus' lectures must have been given in some centre of philosophical schools and of learning. He never opposes Roman relations to those of the place where he is speaking, as he does in regard to Athens and Alexandria. He uses the name "Romans" only three times, once comparing them to the Rhodians, once to the Persians, and once in general to other nations. In the first two of these references, the expression "among the Romans" in the first part of the antithesis is followed by the expression, "among us," in the second part, which Haas understands to be synonymous. The third reference is in regard to a Roman law, and the use of the word 'Roman' does not at all show that Sextus was not then in Rome. The character of the laws referred to by Sextus as [Greek: par' haemin] shows that they were always Roman laws, and his definition of law is especially a definition of Roman law. This argument might, it would seem, apply to any part of the Roman Empire, but Haas claims that the whole relation of law to custom as treated of by Sextus, and all his statements of customs forbidden at that time by law, point to Rome as the place of his residence. Further, Haas considers the Herodotus mentioned by Galen as a prominent physician in Rome, to have been the predecessor and master of Sextus, in whose place Sextus says that he is teaching. Haas also thinks that Sextus' refutation of the identity of Pyrrhonism with Empiricism evidently refers to a paragraph in Galen's Subfiguratio Empirica, which would be natural if the Hypotyposes were written shortly after Galen's Sub. Em., and in the same place. Further, Hippolytus, who wrote in or near Rome very soon after the time of Sextus, apparently used the Hypotyposes, which would be more natural if he wrote in the same place. According to Haas, every thing in internal evidence, and outward testimony, points to Rome as having been the city where Sextus occupied his position as the head of the Sceptical School.
 Haas Op. cit. p. 15.
 Hyp. I. 149, 152; III. 211.
 Hyp. I. 146.
 Galen de puls. IV. 11; Bd. VIII. 751.
 Hyp. III. 120.
 Galen Sub. Em. 123 B-126 D. (Basileae, 1542).
Coming now to the position of Pappenheim on this subject, we find that he takes very decided ground against the seat of the Sceptical School having been in Rome, even for a short time, in his latest publication regarding it. This opinion is the result of late study on the part of Pappenheim, for in his work on the Lebensverhaeltnisse des Sextus Empiricus Berlin 1875, he says, "Dass Herodotus in Rom lebte sagt Galen. Vermuthlich auch Sextus." His reasons given in the later article for not connecting the Sceptical School at all with Rome are as follows. He finds no proof of the influence of Scepticism in Rome, as Cicero remarks that Pyrrhonism is extinct, and he also gives weight to the well-known sarcastic saying of Seneca, Quis est qui tradat praecepta Pyrrhonis! While Haas claims that Sextus would naturally seek one of the centres of dogmatism, in order most effectively to combat it, Pappenheim, on the contrary, contends that it would have been foolishness on the part of Sextus to think of starting the Sceptical School in Rome, where Stoicism was the favored philosophy of the Roman Emperors; and when either for the possible reason of strife between the Empirical and Methodical Schools, or for some other cause, the Pyrrhonean School was removed from Alexandria, Pappenheim claims that all testimony points to the conclusion that it was founded in some city of the East. The name of Sextus is never known in Roman literature, but in the East, on the contrary, literature speaks for centuries of Sextus and Pyrrho. The Hypotyposes, especially, were well-known in the East, and references to Sextus are found there in philosophical and religious dogmatic writings. The Emperor Julian makes use of the works of Sextus, and he is frequently quoted by the Church Fathers of the Eastern Church. Pappenheim accordingly concludes that the seat of Pyrrhonism after the school was removed from Alexandria, was in some unknown city of the East.
 Pappenheim Sitz der Skeptischen Schule. Archiv fuer Geschichte der Phil. 1888.
 Cicero De Orat. III. 17, 62.
 Seneca nat. qu. VII. 32. 2.
 Fabricius de Sexto Empirico Testimonia.
In estimating the weight of these arguments, we must accept with Pappenheim the close connection of Pyrrhonism with Alexandria, and the subsequent influence which it exerted upon the literature of the East. All historical relations tend to fix the permanent seat of Pyrrhonism, after its separation from the Academy, in Alexandria. There is nothing to point to its removal from Alexandria before the time of Menodotus, who is the teacher of Herodotus, and for many reasons to be considered the real teacher of Sextus. It was Menodotus who perfected the Empirical doctrines, and who brought about an official union between Scepticism and Empiricism, and who gave Pyrrhonism in great measure, the eclat that it enjoyed in Alexandria, and who appears to have been the most powerful influence in the school, from the time of Aenesidemus to that of Sextus. Furthermore, Sextus' familiarity with Alexandrian customs bears the imprint of original knowledge, and he cannot, as Zeller implies, be accepted as simply quoting. One could hardly agree with Zeller, that the familiarity shown by Sextus with the customs of both Alexandria and Rome in the Hypotyposes does not necessarily show that he ever lived in either of those places, because a large part of his works are compilations from other books; but on the contrary, the careful reader of Sextus' works must find in all of them much evidence of personal knowledge of Alexandria, Athens and Rome.
 Diog. IX. 12, 116.
 Zeller Op. cit. III. p. 39.
A part of Sextus' books also may have been written in Alexandria. [Greek: Pros phusikous] could have been written in Alexandria. If these were also lectures, then Sextus taught in Alexandria as well as elsewhere. The history of Eastern literature for the centuries immediately following the time of Sextus, showing as it does in so many instances the influence of Pyrrhonism, and a knowledge of the Hypotyposes, furnishes us with an incontestable proof that the school could not have been for a long time removed from the East, and the absence of such knowledge in Roman literature is also a strong argument against its long continuance in that city. It would seem, however, from all the data at command, that during the years that the Sceptical School was removed from Alexandria, its head quarters were in Rome, and that the Pyrrhonean Hypotyposes were delivered in Rome. Let us briefly consider the arguments in favour of such a hypothesis. Scepticism was not unknown in Rome. Pappenheim quotes the remark of Cicero that Pyrrhonism was long since dead, and the sarcasm of Seneca, Quis est qui tradat praecepta Pyrrhonis? as an argument against the knowledge of Pyrrhonism in Rome. We must remember, however, that in Cicero's time Aenesidemus had not yet separated himself from the Academy; or if we consider the Lucius Tubero to whom Aenesidemus dedicated his works, as the same Lucius Tubero who was the friend of Cicero in his youth, and accordingly fix the date of Aenesidemus about 50 B.C., even then Aenesidemus' work in Alexandria was too late to have necessarily been known to Cicero, whose remark must have been referred to the old school of Scepticism. Should we grant, however, that the statements of Cicero and Seneca prove that in their time Pyrrhonism was extinct in Rome, they certainly do not show that after their death it could not have again revived, for the Hypotyposes were delivered more than a century after the death of Seneca. There are very few writers in Aenesidemus' own time who showed any influence of his teachings. This influence was felt later, as Pyrrhonism became better known. That Pyrrhonism received some attention in Rome before the time of Sextus is nevertheless demonstrated by the teachings of Favorinus there. Although Favorinus was known as an Academician, the title of his principal work was [Greek: tous philosophoumenous auto ton logon, hon aristoi hoi Purrhoneioi]. Suidas calls Favorinus a great author and learned in all science and philosophy, and Favorinus made Rome the centre of his teaching and writing. His date is fixed by Zeller at 80-150 A.D., therefore Pyrrhonism was known in Rome shortly before the time of Sextus.
 Pappenheim Sitz der Skeptischen Schule; Archiv fuer Geschichte der Phil., 1888; Adv. Math. X. 15, 95.
 Zeller Op. cit. III. 10.
 Zeller Op. cit. p. 63.
 Zeller Op. cit. p. 67.
 Brochard Op. cit. 329.
The whole tone of the Hypotyposes, with the constant references to the Stoics as living present opponents, shows that these lectures must have been delivered in one of the centres of Stoicism. As Alexandria and Athens are out of the question, all testimony points to Rome as having been the seat of the Pyrrhonean School, for at least a part of the time that Sextus was at its head. We would then accept the teacher of Sextus, in whose place he says he taught, as the Herodotus so often referred to by Galen who lived in Rome. Sextus' frequent references to Asclepiades, whom he mentions ten different times by name in his works, speak in favour of Rome in the matter under discussion, as Asclepiades made that city one of the centres of medical culture. On the other hand, the fact that there is no trace of the Hypotyposes in later Roman literature, with the one exception of the works of Hippolytus, as opposed to the wide-spread knowledge of them shown in the East for centuries, is incontestable historical proof that the Sceptical School could not long have had its seat at Rome. From the two passages given above from Sextus' work against physics, he must either have written that book in Alexandria, it would seem, or have quoted those passages from some other work. May we not then conclude, that Sextus was at the head of the school in Rome for a short time, where it may have been removed temporarily, on account of the difficulty with the Empiricists, implied in Hyp. I. 236-241, or in order to be better able to attack the Stoics, but that he also taught in Alexandria, where the real home of the school was certainly found? There it probably came to an end about fifty years after the time of Sextus, and from that centre the Sceptical works of Sextus had their wide-spread influence in the East.
 Galen VIII. 751.
 Bekker Index.
The books of Sextus Empiricus furnish us with the best and fullest presentation of ancient Scepticism which has been preserved to modern times, and give Sextus the position of one of the greatest men of the Sceptical School. His works which are still extant are the Pyrrhonean Hypotyposes in three volumes, and the two works comprising eleven books which have been united in later times under the title of [Greek: pros mathematikous], one of which is directed against the sciences in general, and the other against the dogmatic philosophers. The six books composing the first of these are written respectively against grammarians, rhetoricians, geometricians, arithmeticians, astronomers and musicians. The five books of the latter consist of two against the logicians, two against physics, and one against systems of morals. If the last short work of the first book directed against the arithmeticians is combined with the one preceding against the geometricians, as it well could be, the two works together would be divided into ten different parts; there is evidence to show that in ancient times such a division was made. There were two other works of Sextus which are now lost, the medical work before referred to, and a book entitled [Greek: peri psuches]. The character of the extant works of Sextus is similar, as they are all directed either against science or against the dogmatics, and they all present the negative side of Pyrrhonism. The vast array of arguments comprising the subject-matter, often repeated in the same and different forms, are evidently taken largely from the Sceptical works which Sextus had resource to, and are, in fact, a summing up of all the wisdom of the Sceptical School. The style of these books is fluent, and the Greek reminds one of Plutarch and Thucydides, and although Sextus does not claim originality, but presents in all cases the arguments of the Sceptic, yet the illustrations and the form in which the arguments are presented, often bear the marks of his own thought, and are characterized here and there by a wealth of humor that has not been sufficiently noticed in the critical works on Sextus. Of all the authors who have reviewed Sextus, Brochard is the only one who seems to have understood and appreciated his humorous side.
We shall now proceed to the consideration of the general position and aim of Pyrrhonism.
 Diog. IX. 12, 116.
The Position and Aim of Pyrrhonism.
The first volume of the Pyrrhonean Hypotyposes gives the most complete statement found in any of the works of Sextus Empiricus of the teachings of Pyrrhonism and its relation to other schools of philosophy. The chief source of the subject-matter presented is a work of the same name by Aenesidemus, either directly used by Sextus, or through the writings of those who followed Aenesidemus. The comprehensive title [Greek: Purrhoneioi hupotuposeis] was very probably used in general to designate courses of lectures given by the leaders of the Sceptical School.
In the opening chapters of the Hypotyposes Sextus undertakes to define the position and aim of Pyrrhonism. In introducing his subject he treats briefly of the differences between philosophical schools, dividing them into three classes; those which claim that they have found the truth, like the schools of Aristotle and Epicurus and the Stoics; those which deny the possibility of finding it, like that of the Academicians; and those that still seek it, like the Sceptical School. The accusation against the Academicians, that they denied the possibility of finding the truth, was one that the Sceptics were very fond of making. We shall discuss the justice of it later, simply remarking here, that to affirm the "incomprehensibility of the unknown," was a form of expression that the Pyrrhonists themselves were sometimes betrayed into, notwithstanding their careful avoidance of dogmatic statements.
 Diog. IX. 11, 78.
 Hyp. I. 3, 4.
 Adv. Math. VIII. 191.
After defining the three kinds of philosophy as the Dogmatic, the Academic and the Sceptic, Sextus reminds his hearers that he does not speak dogmatically in anything that he says, but that he intends simply to present the Sceptical arguments historically, and as they appear to him. He characterizes his treatment of the subject as general rather than critical, including a statement of the character of Scepticism, its idea, its principles, its manner of reasoning, its criterion and aim, and a presentation of the Tropes, or aspects of doubt, and the Sceptical formulae and the distinction between Scepticism and the related schools of philosophy.
The result of all the gradual changes which the development of thought had brought about in the outward relations of the Sceptical School, was to increase the earnestness of the claim of the Sceptics to be simply followers of Pyrrho, the great founder of the movement. In discussing the names given to the Sceptics, Sextus gives precedence very decidedly to the title "Pyrrhonean," because Pyrrho appears the best representative of Scepticism, and more prominent than all who before him occupied themselves with it.
It was a question much discussed among philosophers in ancient times, whether Pyrrhonism should be considered a philosophical sect or not. Thus we find that Hippobotus in his work entitled [Greek: peri haireseon], written shortly before our era, does not include Pyrrhonism among the other sects. Diogenes himself, after some hesitation remarking that many do not consider it a sect, finally decides to call it so.
 Hyp. I. 5, 6.
 Hyp. I. 7.
 Diog. Pro. 19.
 Diog. Pro. 20.
Sextus in discussing this subject calls Scepticism an [Greek: agoge], or a movement, rather than a [Greek: hairesis], saying that Scepticism is not a sect, if that word implies a systematic arrangement of dogmas, for the Sceptic has no dogmas. If, however, a sect may mean simply the following of a certain system of reasoning according to what appears to be true, then Scepticism is a sect. From a quotation given later on by Sextus from Aenesidemus, we know that the latter used the term [Greek: agoge]. Sextus gives also the other titles, so well known as having been applied to Scepticism, namely, [Greek: zetetike], [Greek: ephektike], and [Greek: aporetike]. The [Greek: dunamis] of Scepticism is to oppose the things of sense and intellect in every possible way to each other, and through the equal weight of things opposed, or [Greek: isostheneia], to reach first the state of suspension of judgement, and afterwards ataraxia, or "repose and tranquillity of soul." The purpose of Scepticism is then the hope of ataraxia, and its origin was in the troubled state of mind induced by the inequality of things, and uncertainty in regard to the truth. Therefore, says Sextus, men of the greatest talent began the Sceptical system by placing in opposition to every argument an equal one, thus leading to a philosophical system without a dogma, for the Sceptic claims that he has no dogma. The Sceptic is never supposed to state a decided opinion, but only to say what appears to him. Even the Sceptical formulae, such as "Nothing more," or "I decide nothing," or "All is false," include themselves with other things. The only statements that the Sceptic can make, are in regard to his own sensations. He cannot deny that he is warm or cold or hungry.
 Hyp. I. 15, 17.
 Hyp. I. 210.
 Hyp. I. 7; Diog. IX. 11, 70.
 Hyp. I. 8.
 Hyp. I. 10.
 Hyp. I. 12.
 Hyp. I. 14.
 Hyp. I. 14.
Sextus replies to the charge that the Sceptics deny phenomena by refuting it. The Sceptic does not deny phenomena, because they are the only criteria by which he can regulate his actions. "We call the criterion of the Sceptical School the phenomenon, meaning by this name the idea of it." Phenomena are the only things which the Sceptic does not deny, and he guides his life by them. They are, however, subjective. Sextus distinctly affirms that sensations are the phenomena, and that they lie in susceptibility and voluntary feeling, and that they constitute the appearances of objects. We see from this that Sextus makes the only reality to consist in subjective experience, but he does not follow this to its logical conclusion, and doubt the existence of anything outside of mind. He rather takes for granted that there is a something unknown outside, about which the Sceptic can make no assertions. Phenomena are the criteria according to which the Sceptic orders his daily life, as he cannot be entirely inactive, and they affect life in four different ways. They constitute the guidance of nature, the impulse of feeling; they give rise to the traditions of customs and laws, and make the teaching of the arts important. According to the tradition of laws and customs, piety is a good in daily life, but it is not in itself an abstract good. The Sceptic of Sextus' time also inculcated the teaching of the arts, as indeed must be the case with professing physicians, as most of the leading Sceptics were. Sextus says, "We are not without energy in the arts which we undertake." This was a positive tendency which no philosophy, however negative, could escape, and the Sceptic tried to avoid inconsistency in this respect, by separating his philosophy from his theory of life. His philosophy controlled his opinions, and his life was governed by phenomena.
 Hyp. I. 19.
 Hyp. I. 19.
 Hyp. I. 22; Diog. IX. 11, 105.
 Hyp. I. 22.
 Hyp. I. 23.
 Hyp. I. 24.
The aim of Pyrrhonism was ataraxia in those things which pertain to opinion, and moderation in the things which life imposes. In other words, we find here the same natural desire of the human being to rise above and beyond the limitations which pain and passion impose, which is expressed in other forms, and under other names, in other schools of philosophy. The method, however, by which ataraxia or peace of mind could be reached, was peculiar to the Sceptic. It is a state of psychological equilibrium, which results from the equality of the weight of different arguments that are opposed to each other, and the consequent impossibility of affirming in regard to either one, that it is correct. The discovery of ataraxia was, in the first instance, apparently accidental, for while the Sceptic withheld his opinion, unable to decide what things were true, and what things were false, ataraxia fortunately followed. After he had begun to philosophize, with a desire to discriminate in regard to ideas, and to separate the true from the false during the time of [Greek: epoche], or suspension of judgement, ataraxia followed as if by chance, as the shadow follows the body.
 Hyp. I. 25.
 Hyp. I. 26.
 Hyp. I. 26.
 Diog. IX. 11, 107.
 Hyp. I. 29.
The Sceptic in seeking ataraxia in the things of opinion, does not entirely escape from suffering from his sensations. He is not wholly undisturbed, for he is sometimes cold and hungry, and so on. He claims, nevertheless, that he suffers less than the dogmatist, who is beset with two kinds of suffering, one from the feelings themselves, and also from the conviction that they are by nature an evil. To the Sceptic nothing is in itself either an evil or a good, and so he thinks that "he escapes from difficulties easier." For instance, he who considers riches a good in themselves, is unhappy in the loss of them, and in possession of them is in fear of losing them, while the Sceptic, remembering the Sceptical saying "No more," is untroubled in whatever condition he may be found, as the loss of riches is no more an evil than the possession of them is a good. For he who considers anything good or bad by nature is always troubled, and when that which seemed good is not present with him, he thinks that he is tortured by that which is by nature bad, and follows after what he thinks to be good. Having acquired it, however, he is not at rest, for his reason tells him that a sudden change may deprive him of this thing that he considers a good. The Sceptic, however, endeavours neither to avoid nor seek anything eagerly.
 Hyp. I. 30.
 Hyp. I. 30.
 Hyp. I. 30; Diog. IX. 11, 61.
 Adv. Math. XI. 146-160.
 Hyp. I. 27.
 Hyp. I. 28.
Ataraxia came to the Sceptic as success in painting the foam on a horse's mouth came to Apelles the painter. After many attempts to do this, and many failures, he gave up in despair, and threw the sponge at the picture that he had used to wipe the colors from the painting with. As soon as it touched the picture it produced a representation of the foam. Thus the Sceptics were never able to attain to ataraxia by examining the anomaly between the phenomena and the things of thought, but it came to them of its own accord just when they despaired of finding it.
The intellectual preparation for producing ataraxia, consists in placing arguments in opposition to each other, both in regard to phenomena, and to things of the intellect. By placing the phenomenal in opposition to the phenomenal, the intellectual to the intellectual, and the phenomenal to the intellectual, and vice versa, the present to the present, past, and future, one will find that no argument exists that is incontrovertible. It is not necessary to accept any statement whatever as true, and consequently a state of [Greek: epoche] may always be maintained. Although ataraxia concerns things of the opinion, and must be preceded by the intellectual process described above, it is not itself a function of the intellect, or any subtle kind of reasoning, but seems to be rather a unique form of moral perfection, leading to happiness, or is itself happiness.
 Hyp. I. 28, 29.
 Hyp. I. 32-35.
It was the aim of Scepticism to know nothing, and to assert nothing in regard to any subject, but at the same time not to affirm that knowledge on all subjects is impossible, and consequently to have the attitude of still seeking. The standpoint of Pyrrhonism was materialistic. We find from the teachings of Sextus that he affirmed the non-existence of the soul, or the ego, and denied absolute existence altogether. The introductory statements of Diogenes regarding Pyrrhonism would agree with this standpoint.
There is no criterion of truth in Scepticism. We cannot prove that the phenomena represent objects, or find out what the relation of phenomena to objects is. There is no criterion to tell us which one is true of all the different representations of the same object, and of all the varieties of sensation that arise through the many phases of relativity of the conditions which control the character of the phenomena.
Every effort to find the truth can deal only with phenomena, and absolute reality can never be known.
 Adv. Math. VII. 55; Hyp. II. 32.
 Adv. Math. XI. 140.
 Diog. IX. 11, 61.
The Sceptical Tropes.
The exposition of the Tropes of Pyrrhonism constitutes historically and philosophically the most important part of the writings of Sextus Empiricus. These Tropes represent the sum total of the wisdom of the older Sceptical School, and were held in high respect for centuries, not only by the Pyrrhoneans, but also by many outside the narrow limits of that School. In the first book of the Hypotyposes Sextus gives two classes of Tropes, those of [Greek: epoche] and the eight Tropes of Aenesidemus against Aetiology.
The Tropes of [Greek: epoche] are arranged in groups of ten, five and two, according to the period of the Sceptical School to which they belong; the first of these groups is historically the most important, or the Ten Tropes of [Greek: epoche], as these are far more closely connected with the general development of Scepticism, than the later ones. By the name [Greek: tropos] or Trope, the Sceptic understood a manner of thought, or form of argument, or standpoint of judgement. It was a term common in Greek philosophy, used in this sense, from the time of Aristotle. The Stoics, however, used the word with a different meaning from that attributed to it by the Sceptics. Stephanus and Fabricius translate it by the Latin word modus and [Greek: tropos] also is often used interchangeably with the word [Greek: logos] by Sextus, Diogenes Laertius, and others; sometimes also as synonymous with [Greek: topos], and [Greek: typos] is found in the oldest edition of Sextus. Diogenes defines the word as the standpoint, or manner of argument, by which the Sceptics arrived at the condition of doubt, in consequence of the equality of probabilities, and he calls the Tropes, the ten Tropes of doubt. All writers on Pyrrhonism after the time of Aenesidemus give the Tropes the principal place in their treatment of the subject. Sextus occupies two thirds of the first book of the Hypotyposes in stating and discussing them; and about one fourth of his presentation of Scepticism is devoted to the Tropes by Diogenes. In addition to these two authors, Aristocles the Peripatetic refers to them in his attack on Scepticism. Favorinus wrote a book entitled Pyrrhonean Tropes, and Plutarch one called The Ten ([Greek: topoi]) Topes of Pyrrho. Both of these latter works are lost.
 Pappenheim Erlauterung Pyrrh. Grundzugen, p. 35.
 Diog I. 76; Adv. Math. VIII. 227.
 Fabricius, Cap. XIV. 7.
 Hyp. I. 36.
 Fabricius on Hyp. I. 36; Cap. XIV. G.
 Diog. IX. 11, 79-108.
 Aristocles Euseb. praep. ev. X. 14, 18.
 Fabricius on Hyp. I. 36.
All authorities unite in attributing to Aenesidemus the work of systematizing and presenting to the world the ten Tropes of [Greek: epoche]. He was the first to conceive the project of opposing an organized philosophical system of Pyrrhonism to the dogmatism of his contemporaries. Moreover, the fact that Diogenes introduces the Tropes into his life of Pyrrho, does not necessarily imply that he considered Pyrrho their author, for Diogenes invariably combines the teachings of the followers of a movement with those of the founders themselves; he gives these Tropes after speaking of Aenesidemus' work entitled Pyrrhonean Hypotyposes, and apparently quotes from this book, in giving at least a part of his presentation of Pyrrhonism, either directly or through, the works of others. Nietzsche proposes a correction of the text of Diogenes IX. 11, 79, which would make him quote the Tropes from a book by Theodosius, author of a commentary on the works of Theodas. No writer of antiquity claims for the Tropes an older source than the books of Aenesidemus, to whom Aristocles also attributes them. They are not mentioned in Diogenes' life of Timon, the immediate disciple of Pyrrho. Cicero has no knowledge of them, and does not refer to them in his discussion of Scepticism.
 Compare Saisset Op. cit. p. 78.
 Brochard Op. cit. 254, Note 4.
 Aristocles Eus. praep. ev. XIV. 18. 8.
Aenesidemus was undoubtedly the first to formulate these Tropes, but many things tend to show that they resulted, in reality, from the gradual classification of the results of the teachings of Pyrrho, in the subsequent development of thought from his own time to that of Aenesidemus. The ideas contained in the Tropes were not original with Aenesidemus, but are more closely connected with the thought of earlier times. The decidedly empirical character of the Tropes proves this connection, for the eight Tropes of Aetiology, which were original with Aenesidemus, bear a far stronger dialectic stamp, thus showing a more decided dialectic influence of the Academy than is found in the Tropes of [Greek: epoche]. Many of the illustrations given of the Tropes also, testify to a time of greater antiquity than that of Aenesidemus. The name Trope was well known in ancient times, and the number ten reminds us of the ten opposing principles of Pythagoras, and the ten categories of Aristotle, the fourth of which was the same as the eighth Trope. The terminology, however, with very few exceptions, points to a later period than that of Pyrrho. Zeller points out a number of expressions in both Diogenes' and Sextus' exposition of the Tropes, which could not date back farther than the time of Aenesidemus. One of the most striking features of the whole presentation of the Tropes, especially as given by Sextus, is their mosaic character, stamping them not as the work of one person, but as a growth, and also an agglutinous growth, lacking very decidedly the symmetry of thought that the work of one mind would have shown.
 Zeller Op. cit. p. 25.
At the time of the separation of Pyrrhonism from the Academy, no other force was as strong in giving life to the school as the systematic treatment by Aenesidemus of the Ten Tropes of [Greek: epoche]. The reason of this is evident. It was not that the ideas of the Sceptical Tropes were original with Aenesidemus, but because a definite statement of belief is always a far more powerful influence than principles which are vaguely understood and accepted. There is always, however, the danger to the Sceptic, in making a statement even of the principles of Scepticism, that the psychological result would be a dogmatic tendency of mind, as we shall see later was the case, even with Aenesidemus himself. That the Sceptical School could not escape the accusation of dogmatizing, from the Dogmatics, even in stating the grounds of their Scepticism, we know from Diogenes. To avoid this dogmatic tendency of the ten Tropes, Sextus makes the frequent assertion that he does not affirm things to be absolutely true, but states them as they appear to him, and that they may be otherwise from what he has said.
 Diog. IX. 11, 102.
 Hyp. I. 4, 24.
Sextus tells us that "Certain Tropes, ten in number, for producing the state of [Greek: epoche] have been handed down from the older Sceptics." He refers to them in another work as the "Tropes of Aenesidemus." There is no evidence that the substance of these Tropes was changed after the time of Aenesidemus, although many of the illustrations given by Sextus must have been of a later date, added during the two centuries that elapsed between the time of Aenesidemus and Sextus. In giving these Tropes Sextus does not claim to offer a systematic methodical classification, and closes his list of them, in their original concise form, with the remark, "We make this order ourselves." The order is given differently by Diogenes, and also by Favorinus. The Trope which Sextus gives as the tenth is the fifth given by Diogenes, the seventh by Sextus is the eighth given by Diogenes, the fifth by Sextus, the seventh by Diogenes, the tenth by Diogenes, the eighth by Sextus. Diogenes says that the one he gives as the ninth Favorinus calls the eighth, and Sextus and Aenesidemus the tenth. This statement does not correspond with the list of the Tropes which Sextus gives, proving that Diogenes took some other text than that of Sextus as his authority. The difference in the order of the Tropes shows, also, that the order was not considered a matter of great importance. There is a marked contrast in the spirit of the two presentations of the Tropes given by Sextus and Diogenes. The former gives them not only as an orator, but as one who feels that he is defending his own cause, and the school of which he is the leader, against mortal enemies, while Diogenes relates them as an historian.
 Hyp. I. 36.
 Adv. Math. VII. 345.
 Hyp. I. 38.
 Diog. IX. 11, 87.
 Diog. IX. 11, 87.
Pappenheim tries to prove that Aenesidemus originally gave only nine Tropes in his Pyrrhonean Hypotyposes, as Aristocles mentions only nine in referring to the Tropes of Aenesidemus, and that the tenth was added later. Had this been the case, however, the fact would surely have been mentioned either by Diogenes or Sextus, who both refer to the ten Tropes of Aenesidemus.
The Tropes claim to prove that the character of phenomena is so relative and changeable, that certain knowledge cannot be based upon them, and as we have shown, there is no other criterion of knowledge for the Sceptic than phenomena. All of the Tropes, except the tenth, are connected with sense-perception, and relate to the difference of the results obtained through the senses under different circumstances. They may be divided into two classes, i.e., those based upon differences of our physical organism, and those based upon external differences. To the first class belong the first, second, third and fourth; to the second class, the fifth, sixth, seventh and eighth, and also the ninth. The eighth, or that of relation, is applied objectively both by Sextus and Diogenes in their treatment of the Tropes, and is not used for objects of thought alone, but principally to show the relation of outward objects to each other. The tenth is the only one which has a moral significance, and it has also a higher subjective value than the others; it takes its arguments from an entirely different sphere of thought, and deals with metaphysical and religious contradictions in opinion, and with the question of good and evil. That this Trope is one of the oldest, we know from its distinct mention in connection with the foundation theories of Pyrrho, by Diogenes. In treating of the subjective reasons for doubt as to the character of external reality, the Sceptics were very near the denial of all outward reality, a point, however, which they never quite reached.
 Pappenheim, Die Tropen der Griechen, p. 23.
 Hyp. I. 22.
 Diog. IX. 11, 61.
There is evidently much of Sextus' own thought mixed with the illustrations of the Tropes, but it is impossible to separate the original parts from the material that was the common property of the Sceptical School. Many of these illustrations show, however, perfect familiarity with the scientific and medical teachings of the time. Before entering upon his exposition of the Tropes, Sextus gives them in the short concise form in which they must first have existed—
(i) Based upon the variety of animals.
(ii) Based upon the differences between men.
(iii) Based upon differences in the constitution of the sense organs.
(iv) Based upon circumstances.
(v) Based upon position, distance and place.
(vi) Based upon mixtures.
(vii) Based upon the quantities and constitutions of objects.
(ix) Based upon frequency or rarity of occurences.
(x) Based upon systems, customs and laws, mythical beliefs, and dogmatic opinions.
 Hyp. I. 36-38.
Although Sextus is careful not to dogmatise regarding the arrangement of the Tropes, yet there is in his classification of them a regular gradation, from the arguments based upon differences in animals to those in man, first considering the latter in relation to the physical constitution, and then to circumstances outside of us, and finally the treatment of metaphysical and moral differences.
The First Trope. That the same mental representations are not found in different animals, may be inferred from their differences in constitution resulting from their different origins, and from the variety in their organs of sense. Sextus takes up the five senses in order, giving illustrations to prove the relative results of the mental representations in all of them, as for example the subjectivity of color and sound. All knowledge of objects through the senses is relative and not absolute. Sextus does not, accordingly, confine the impossibility of certain knowledge to the qualities that Locke regards as secondary, but includes also the primary ones in this statement. The form and shape of objects as they appear to us may be changed by pressure on the eyeball. Furthermore, the character of reflections in mirrors depend entirely on their shape, as the images in concave mirrors are very different from those in convex ones; and so in the same way as the eyes of animals are of different shapes, and supplied with different fluids, the ideas of dogs, fishes, men and grasshoppers must be very different.
 Hyp.. I. 40-61.
 Hyp.. I. 44-46.
 Hyp.. I. 50.
 Hyp.. I. 47.
 Hyp.. I. 49.
In discussing the mental representations of animals of different grades of intelligence, Sextus shows a very good comprehension of the philogenetic development of the organs of sense, and draws the final conclusion that external objects are regarded differently by animals, according to their difference in constitution. These differences in the ideas which different animals have of the same objects are demonstrated by their different tastes, as the things desired by some are fatal to others. The practical illustrations given of this result show a familiarity with natural history, and cognizance of the tastes and habits of many animals, but were probably few of them original with Sextus, unless perhaps in their application; that this train of reasoning was the common property of the Sceptic School, we know from the fact that Diogenes begins his exposition of the first Trope in a way similar to that of Sextus. His illustrations are, however, few and meagre compared with those of Sextus, and the scientific facts used by both of them may mostly be found in other authors of antiquity given in a similar way. The logical result of the reasoning used to explain the first Trope, is that we cannot compare the ideas of the animals with each other, nor with our own; nor can we prove that our ideas are more trustworthy than those of the animals. As therefore an examination of ideas is impossible, any decided opinion about their trustworthiness is also impossible, and this Trope leads to the suspension of judgment regarding external objects, or to [Greek: epoche.]
 Hyp.. I. 54.
 Hyp.. I. 55.
 Hyp.. I. 55-59.
 Diog. IX. 11, 79-80.
 Pappenheim Erlauterung Pyrr. Grundzuege Par. 41.
 Hyp. I. 59.
 Hyp. I. 61.
After reaching this conclusion, Sextus introduces a long chapter to prove that animals can reason. There is no reference to this in Diogenes, but there is other testimony to show that it was a favourite line of argument with the Sceptics. Sextus, however, says that his course of reasoning is different from that of most of the Sceptics on the subject, as they usually applied their arguments to all animals, while he selected only one, namely the dog. This chapter is full of sarcastic attacks on the Dogmatics, and contains the special allusion to the Stoics as the greatest opponents of the Sceptics, which has been before referred to.
Sextus claims with a greater freedom of diction than in some apparently less original chapters, and with a wealth of special illustrations, that the dog is superior to man in acuteness of perception, that he has the power of choice, and possesses an art, that of hunting, and, also, is not deprived of virtue, as the true nature of virtue is to show justice to all, which the dog does by guarding loyally those who are kind to him, and keeping off those who do evil. The reasoning power of this animal is proved by the story taken from Chrysippus, of the dog that came to a meeting of three roads in following a scent. After seeking the scent in vain in two of the roads, he takes the third road without scenting it as a result of a quick process of thought, which proves that he shares in the famous dialectic of Chrysippus, the five forms of [Greek: anapodeiktoi logoi,] of which the dog chooses the fifth. Either A or B or C, not A or B, therefore C.
 Hyp. I. 238.
 Compare Brochard Op. cit. 256.
 Hyp. I. 62-63.
 Hyp. I. 65.
 Hyp. I. 64.
 Hyp. I. 66.
 Hyp. I. 67.
 Hyp. I. 67.
 Hyp. I. 69; Hyp. II. 166; Diog. VII. 1, 79.
The dog and other irrational animals may also possess spoken language, as the only proof that we have to the contrary, is the fact that we cannot understand the sounds that they make. We have an example in this chapter of the humor of Sextus, who after enlarging on the perfect character of the dog, remarks, "For which reason it seems to me some philosophers have honoured themselves with the name of this animal," thus making a sarcastic allusion to the Cynics, especially Antisthenes.
 Hyp. I. 74.
 Hyp. I. 72.
 Diog. VI. 1, 13.
The Second Trope. Passing on to the second Trope, Sextus aims to prove that even if we leave the differences of the mental images of animals out of the discussion, there is not a sufficient unanimity in the mental images of human beings to allow us to base any assertions upon them in regard to the character of external objects. He had previously announced that he intended to oppose the phenomenal to the intellectual "in any way whatever," so he begins here by referring to the two parts of which man is said to be composed, the soul and the body, and proceeds to discuss the differences among men in sense-perception and in opinion. Most of the illustrations given of differences in sense-perception are medical ones; of the more general of these I will note the only two which are also given by Diogenes in his exposition of this Trope, viz., Demophon, Alexander's table waiter, who shivered in the sun, and Andron the Argive, who was so free from thirst that he travelled through the desert of Libya without seeking a drink. Some have reasoned from the presence of the first of these illustrations in the exposition of the Tropes, that a part of this material at least goes back to the time of Pyrrho, as Pyrrho from his intimacy with Alexander, when he accompanied him to India, had abundant opportunities to observe the peculiarities of his servant Demophon. The illustration of Andron the Argive is taken from Aristotle, according to Diogenes.
 Hyp. I. 79.
 Hyp. I. 8.
 Hyp. I. 80.
 Diog. IX. 11, 80-81.
 Compare Pyrrhon et le Scepticism primitive, Revue phil., Paris 1885, No. 5; Victor Brochard, p. 521.
 Diog. IX. 11, 81.
Passing on to differences of opinion, we have another example of the sarcastic humor of Sextus, as he refers to the [Greek: physiognomonike sophia] as the authority for believing that the body is a type of the soul. As the bodies of men differ, so the souls also probably differ. The differences of mind among men is not referred to by Diogenes, except in the general statement that they choose different professions; while Sextus elaborates this point, speaking of the great differences in opposing schools of philosophy, and in the objects of choice and avoidance, and sources of pleasure for different men. The poets well understand this marked difference in human desires, as Homer says,
"One man enjoys this, another enjoys that."
Sextus also quotes the beautiful lines of Pindar,
"One delights in getting honours and crowns through stormfooted horses, Others in passing life in rooms rich in gold, Another safe travelling enjoys, in a swift ship, on a wave of the sea."
 Hyp. I. 85.
 Hyp. I. 87-89.
 Hyp. I. 86.
The Third Trope. The third Trope limits the argument to the sense-perceptions of one man, a Dogmatic, if preferred, or to one whom the Dogmatics consider wise, and states that as the ideas given by the different sense organs differ radically in a way that does not admit of their being compared with each other, they furnish no reliable testimony regarding the nature of objects. "Each of the phenomena perceived by us seems to present itself in many forms, as the apple, smooth, fragrant brown and sweet." The apple was evidently the ordinary example given for this Trope, for Diogenes uses the same, but in a much more condensed form, and not with equal understanding of the results to be deduced from it. The consequence of the incompatibility of the mental representations produced through the several sense organs by the apple, may be the acceptance of either of the three following propositions: (i) That only those qualities exist in the apple which we perceive. (ii) That more than these exist. (iii) That even those perceived do not exist. Accordingly, any experience which can give rise to such different views regarding outward objects, cannot be relied upon as a testimony concerning them.
 Hyp. I. 90.
 Hyp. I. 94.
 Diog. IX. 11 81.
 Hyp. I. 99.
The non-homogeneous nature of the mental images connected with the different sense organs, as presented by Sextus, reminds us of the discussion of the same subject by Berkeley in his Theory of Vision.
Sextus says that a man born with less than the usual number of senses, would form altogether different ideas of the external world than those who have the usual number, and as our ideas of objects depend on our mental images, a greater number of sense organs would give us still different ideas of outward reality. The strong argument of the Stoics against such reasoning as this, was their doctrine of pre-established harmony between nature and the soul, so that when a representation is produced in us of a real object, a [Greek: kataleptike phantasia], by this representation the soul grasps a real existence. There is a [Greek: logos] in us which is of the same kind, [Greek: syngenos], or in relation to all nature. This argument of pre-established harmony between the faculties of the soul and the objects of nature, is the one that has been used in all ages to combat philosophical teaching that denies that we apprehend the external world as it is. It was used against Kant by his opponents, who thought in this way to refute his teachings. The Sceptics could not, of course, accept a theory of nature that included the soul and the external world in one harmonious whole, but Sextus in his discussion of the third Trope does not refute this argument as fully as he does later in his work against logic. He simply states here that philosophers themselves cannot agree as to what nature is, and furthermore, that a philosopher himself is a part of the discord, and to be judged, rather than being capable of judging, and that no conclusion can be reached by those who are themselves an element of the uncertainty.
 Hyp. I. 96-97.
 Adv. Math. VII. 93.
 Ueberweg Op. cit. 195.
 Adv. Math. VII. 354.
 Hyp. I. 98-99.
The Fourth Trope. This Trope limits the argument to each separate sense, and the effect is considered of the condition of body and mind upon sense-perception in relation to the several sense-organs. The physical states which modify sense-perception are health and illness, sleeping and waking, youth and age, hunger and satiety, drunkenness and sobriety. All of these conditions of the body entirely change the character of the mental images, producing different judgments of the color, taste, and temperature of objects, and of the character of sounds. A man who is asleep is in a different world from one awake, the existence of both worlds being relative to the condition of waking and sleeping.
The subjective states which Sextus mentions here as modifying the character of the mental representations are hating or loving, courage or fear, sorrow or joy, and sanity or insanity. No man is ever twice in exactly the same condition of body or mind, and never able to review the differences of his ideas as a sum total, for those of the present moment only are subject to careful inspection. Furthermore, no one is free from the influence of all conditions of body or mind, so that he can be unbiassed to judge his ideas, and no criterion can be established that can be shown to be true, but on the contrary, whatever course is pursued on the subject, both the criterion and the proof will be thrown into the circulus in probando, for the truth of each rests on the other.
 Hyp. I. 100.
 Hyp. I. 104.
 Hyp. I. 100.
 Hyp. I. 112.
 Hyp. I. 117.
Diogenes gives in part the same illustrations of this Trope, but in a much more condensed form. The marked characteristic of this train of reasoning is the attempt to prove that abnormal conditions are also natural. In referring at first to the opposing states of body and mind, which so change the character of sense-perception, Sextus classifies them according to the popular usage as [Greek: kata physin] and [Greek: para physin]. This distinction was an important one, even with Aristotle, and was especially developed by the Stoics in a broader sense than referring merely to health and sickness. The Stoics, however, considered only normal conditions as being according to nature. Sextus, on the contrary, declares that abnormal states are also conditions according to nature, and just as those who are in health are in a state that is natural to those who are in health, so also those not in health are in a state that is natural to those not in health, and in some respects according to nature. Existence, then, and non-existence are not absolute, but relative, and the world of sleep as really exists for those who are asleep as the things that exist in waking exist, although they do not exist in sleep. One mental representation, therefore, cannot be judged by another, which is also in a state of relation to existing physical and mental conditions. Diogenes states this principle even more decidedly in his exposition of this Trope. "The insane are not in a condition opposed to nature; why they more than we? For we also see the sun as if it were stationary." Furthermore, in different periods of life ideas differ. Children are fond of balls and hoops, while those in their prime prefer other things, and the aged still others. The wisdom contained in this Trope in reference to the relative value of the things most sought after is not original with Sextus, but is found in the more earnest ethical teachings of older writers. Sextus does not, however, draw any moral conclusions from this reasoning, but only uses it as an argument for [Greek: epoche].
 Diog. VII. 1, 86.
 Hyp. I. 103.
 Hyp. I. 104.
 Diog. IX. 11, 82.
 Hyp. I. 106.
The Fifth Trope. This Trope leaves the discussion of the dependence of the ideas upon the physical nature, and takes up the influence of the environment upon them. It makes the difference in ideas depend upon the position, distance, and place of objects, thus taking apparently their real existence for granted. Things change their form and shape according to the distance from which they are observed, and the position in which they stand.
The same light or tone alters decidedly in different surroundings. Perspective in paintings depends on the angle at which the picture is suspended. With Diogenes this Trope is the seventh, and his exposition of it is similar, but as usual, shorter. Both Sextus and Diogenes give the illustration of the neck of the dove differing in color in different degrees of inclination, an illustration used by Protagoras also to prove the relativity of perception by the senses. "The black neck of the dove in the shade appears black, but in the light sunny and purple." Since, then, all phenomena are regarded in a certain place, and from a certain distance, and according to a certain position, each of which relations makes a great difference with the mental images, we shall be obliged also by this Trope to come to the reserving of the opinion.
 Hyp. I. 118.
 Hyp. I. 120.
 Diog. IX. 11, 85.
 Hyp. I. 120; Diog. IX. 11, 86.
 Schol. zu Arist. 60, 18, ed. Brandis; Pappen. Er. Pyrr. Grundzuege, p. 54.
 Hyp. I. 121.
The Sixth Trope. This Trope leads to [Greek: epoche] regarding the nature of objects, because no object can ever be presented to the organs of sense directly, but must always be perceived through some medium, or in some mixture. This mixture may be an outward one, connected with the temperature, or the rarity of the air, or the water surrounding an object, or it may be a mixture resulting from the different humors of the sense-organs. A man with the jaundice, for example, sees colors differently from one who is in health. The illustration of the jaundice is a favorite one with the Sceptics. Diogenes uses it several times in his presentation of Scepticism, and it occurs in Sextus' writings in all, as an illustration, in eight different places. The condition of the organ of the [Greek: hegemonikon], or the ruling faculty, may also cause mixtures. Pappenheim thinks that we have here Kant's idea of a priori, only on a materialistic foundation. A careful consideration of the passage, however, shows us that Sextus' thought is more in harmony with the discoveries of modern psychiatry than with the philosophy of Kant. If the sentence, [Greek: isos de kai aute (he dianoia) epimixian tina idian poieitai pros ta hypo ton aistheseon anangellomena], stood alone, without further explanation, it might well refer to a priori laws of thought, but the explanation which follows beginning with "because" makes that impossible. "Because in each of the places where the Dogmatics think that the ruling faculty is, we see present certain humors, which are the cause of mixtures." Sextus does not advance any opinion as to the place of the ruling faculty in the body, which is, according to the Stoics, the principal part of the soul, where ideas, desires, and reasoning originate, but simply refers to the two theories of the Dogmatics, which claim on the one hand that it is in the brain, and on the other that it is in the heart. This subject he deals with more fully in his work against logic. As, however, he bases his argument, in discussing possible intellectual mixtures in illustration of the sixth Trope, entirely on the condition of the organ of the intellect, it is evident that his theory of the soul was a materialistic one.
 Hyp. I. 124.
 Hyp. I. 125.
 Hyp. I. 126.
 See Index to Bekker's edition of Sextus.
 Papp. Er. Pyr. Gr. p. 55.
 Hyp. I. 128.
 Hyp. I. 128.
 Diog. VII. 1, 159.
 Hyp. I. 128.
 Adv. Math. VII. 313.
The Seventh Trope. This Trope, based upon the quantities and compositions of objects, is illustrated by examples of different kinds of food, drink, and medicine, showing the different effects according to the quantity taken, as the harmfulness and the usefulness of most things depend on their quantity. Things act differently upon the senses if applied in small or large quantities, as filings of metal or horn, and separate grains of sand have a different color and touch from the same taken in the form of a solid. The result is that ideas vary according to the composition of the object, and this Trope also brings to confusion the existence of outward objects, and leads us to reserve our opinion in regard to them. This Trope is illustrated by Diogenes with exceeding brevity.
 Hyp. I. 129-131.
 Hyp. I. 134.
 Diog. IX. 11, 86.
The Eighth Trope. The Trope based upon relation contains, as Sextus rightly remarks, the substance of the other nine, for the general statement of the relativity of knowledge includes the other statements made. The prominence which Sextus gave this Trope in his introduction to the ten Tropes leads one to expect here new illustrations and added arguments for [Greek: epoche]. We find, however, neither of these, but simply a statement that all things are in relation in one of two ways, either directly, or as being a part of a difference. These two kinds of relation are given by Protagoras, and might have been used to good purpose in the introduction to the Tropes, or at the end, to prove that all the others were really subordinate to the eighth. The reasoning is, however simply applied to the relation of objects to each other, and nothing is added that is not found elsewhere where as an argument for [Greek: epoche]. This Trope is the tenth by Diogenes, and he strengthens his reasoning in regard to it, by a statement that Sextus does not directly make, i.e., that everything is in relation to the understanding.
 Hyp. I. 39.
 Hyp. I. 135-140.
 Hyp. I. 135-140.
 Diog. IX. 11, 88.
The Ninth Trope. This is based upon the frequency and rarity of events, and refers to some of the phenomena of nature, such as the rising of the sun, and the sea, as no longer a source of astonishment, while a comet or an earthquake are wonders to those not accustomed to them. The value of objects also depends on their rarity, as for example the value of gold. Furthermore, things may be valuable at one time, and at another not so, according to the frequency and rarity of the occurrence. Therefore this Trope also leads to [Greek: epoche]. Diogenes gives only two illustrations to this Trope, that of the sun and the earthquake.
 Hyp. I. 141-142.
 Hyp. I. 143.
 Hyp. I. 144.
 Diog. IX. 11, 87.
The Tenth Trope. We have already remarked on the difference in the character of the tenth Trope, dealing as it does, not with the ideas of objects, like the other nine Tropes, but with philosophical and religious opinions, and questions of right and wrong. It was the well-known aim of the Sceptics to submit to the laws and customs of the land where they were found, and to conform to certain moral teachings and religious ceremonies; this they did without either affirming or denying the truth of the principles upon which these teachings were based, and also without any passion or strong feeling in regard to them, as nothing in itself can be proved to be good or evil. The tenth Trope accordingly, brings forward contradictions in customs, laws, and the beliefs of different lands, to show that they are also changeable and relative, and not of absolute worth. The foundation-thought of this Trope is given twice by Diogenes, once as we have before stated in his introduction to the life of Pyrrho, and also as one of the Tropes. As it is apparently one of the oldest of the Tropes, it would naturally be much used in discussing with the Stoics, whose philosophy had such a wide ethical significance, and must also have held an important place in the Sceptical School in all metaphysical and philosophical discussions. The definition in the beginning of Sextus' exposition of this Trope Fabricius thinks was taken from Aristotle, of schools, laws, customs, mythical beliefs and dogmatic opinions, and the definition which Diogenes gives of law in his life of Plato is similar. Pappenheim, however, thinks they were taken from the Stoics, perhaps from Chrysippus. The argument is based upon the differences in development of thought, as affecting the standpoint of judgment in philosophy, in morals, and religion, the results of which we find in the widely opposing schools of philosophy, in the variety in religious belief, and in the laws and customs of different countries. Therefore the decisions reached in the world of thought leave us equally in doubt regarding the absolute value of any standards, with those obtained through sense-perception, and the universal conflict of opinion regarding all questions of philosophy and ethics leads us also according to this Trope to the reserving of the opinion. This Trope is the fifth as given by Diogenes, who placed it directly after the first four which relate more especially to human development, while Sextus uses it as the final one, perhaps thinking that an argument based upon the higher powers of man deserves the last place, or is the summation of the other arguments.
 Hyp. I. 24.
 Hyp. III. 235.
 Diog. IX. 11, 61.
 Diog. IX. 11, 83.
 Hyp. I. 145-147.
 Fabricius, Cap. IV. H.
 Diog. III. 86.
 Pappenheim Gr. Pyrr. Grundzuege, p. 50.
 Hyp. I. 163.
 Diog. IX. 11, 83.
Following the exposition of the ten Tropes of the older Sceptics, Sextus gives the five Tropes which he attributes to the "later Sceptics." Sextus nowhere mentions the author of these Tropes. Diogenes, however, attributes them to Agrippa, a man of whom we know nothing except his mention of him. He was evidently one of the followers of Aenesidemus, and a scholar of influence in the Sceptical School, who must have himself had disciples, as Diogenes says, [Greek: hoi peri Agrippan] add to these tropes other five tropes, using the plural verb. Another Sceptic, also mentioned by Diogenes, and a man unknown from other sources, named some of his books after Agrippa. Agrippa is not given by Diogenes in the list of the leaders of the Sceptical School, but his influence in the development of the thought of the School must have been great, as the transition from the ten Tropes of the "older Sceptics" to the five attributed to Agrippa is a marked one, and shows the entrance into the school of a logical power before unknown in it. The latter are not a reduction of the Tropes of Aenesidemus, but are written from an entirely different standpoint. The ten Tropes are empirical, and aim to furnish objective proofs of the foundation theories of Pyrrhonism, while the five are rather rules of thought leading to logical proof, and are dialectic in their character. We find this distinction illustrated by the different way in which the Trope of relativity is treated in the two groups. In the first it points to an objective relativity, but with Agrippa to a general subjective logical principle. The originality of the Tropes of Agrippa does not lie in their substance matter, but in their formulation and use in the Sceptical School. These methods of proof were, of course, not new, but were well known to Aristotle, and were used by the Sceptical Academy, and probably also by Timon, while the [Greek: pros ti] goes back at least to Protagoras. The five Tropes are as follows.
(i) The one based upon discord. (ii) The regressus in infinitum. (iii) Relation. (iv) The hypothetical. (v) The circulus in probando.
Two of these are taken from the old list, the first and the third, and Sextus says that the five Tropes are intended to supplement the ten Tropes, and to show the audacity of the Dogmatics in a variety of ways. The order of these Tropes is the same with Diogenes as with Sextus, but the definitions of them differ sufficiently to show that the two authors took their material from different sources. According to the first one everything in question is either sensible or intellectual, and in attempting to judge it either in life, practically, or "among philosophers," a position is developed from which it is impossible to reach a conclusion. According to the second, every proof requires another proof, and so on to infinity, and there is no standpoint from which to begin the reasoning. According to the third, all perceptions are relative, as the object is colored by the condition of the judge, and the influence of other things around it. According to the fourth, it is impossible to escape from the regressus in infinitum by making a hypothesis the starting point, as the Dogmatics attempt to do. And the fifth, or the circulus in probando, arises when that which should be the proof needs to be sustained by the thing to be proved.
 Hyp. I. 164.
 Diog. IX. 11, 88.
 Diog. IX. 11, 106.
 Diog. IX. 12, 115-116.
 Compare Natorp. Op. cit. p. 302.
 Hyp. I. 177.
 Hyp. I. 165.
 Hyp. I. 166.
 Hyp. I. 167.
 Hyp. I. 168.