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.[9] This Trope is the fifth as given by Diogenes, who placed it directly after the first four which relate more especially to human development,[10] 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.

    [1] Hyp. I. 24.

    [2] Hyp. III. 235.

    [3] Diog.  IX. 11, 61.

    [4] Diog.  IX. 11, 83.

    [5] Hyp. I. 145-147.

    [6] Fabricius, Cap.  IV.  H.

    [7] Diog.  III. 86.

    [8] Pappenheim Gr.  Pyrr.  Grundzuege, p. 50.

    [9] Hyp. I. 163.

    [10] 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."[1] 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][2] 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.[3] Agrippa is not given by Diogenes in the list of the leaders of the Sceptical School, but[4] 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,[5] while the [Greek:  pros ti] goes back at least to Protagoras.  The five Tropes are as follows.