Greek Texts & Translations

The seventh mode has reference to distances, positions, places and the occupants of the places. In this mode things which are thought to be large appear small, square things round ; flat things appear to have projections, straight things to be bent, and colourless coloured. So the sun, on account of its distance, appears small, mountains when far away appear misty and smooth, but when near at hand rugged. 9.11.86 Furthermore, the sun at its rising has a certain appearance, but has a dissimilar appearance when in mid-heaven, and the same body one appearance in a wood and another in open country. The image again varies according to the position of the object, and a dove's neck according to the way it is turned. Since, then, it is not possible to observe these things apart from places and positions, their real nature is unknowable.

The eighth mode is concerned with quantities and qualities of things, say heat or cold, swiftness or slowness, colourlessness or variety of colours. Thus wine taken in moderation strengthens the body, but too much of it is weakening ; and so with food and other things.

The ninth mode has to do with perpetuity, strangeness, or rarity. Thus earthquakes are no surprise to those among whom they constantly take place ; nor is the sun, for it is seen every day. ^note This ninth mode is put eighth by Favorinus and tenth by Sextus and Aenesidemus; moreover the tenth is put eighth by Sextus and ninth by Favorinus.

The tenth mode rests on inter-relation, e.g. between light and heavy, strong and weak, greater and less, up and down. Thus that which is on the right is not so by nature, but is so understood in virtue of its position with respect to something else ; for, if that change its position, the thing is no longer on the right. 9.11.88 Similarly father and brother are relative terms, day is relative to the sun, and all things relative to our mind. Thus relative terms are in and by themselves unknowable. These, then, are the ten modes of perplexity. But Agrippa and his school add to them ^note five other modes, resulting respectively from disagreement, extension ad infinitum, relativity, hypothesis and reciprocal inference. The mode arising from disagreement proves, with regard to any inquiry whether in philosophy or in everyday life, that it is full of the utmost contentiousness and confusion. The mode which involves extension ad infinitum refuses to admit that what is sought to be proved is firmly established, because one thing furnishes the ground for belief in another, and so on ad infinitum. 9.11.89 The mode derived from relativity declares that a thing can never be apprehended in and by itself, but only in connexion with something else. Hence all things are unknowable. The mode resulting from hypothesis arises when people suppose that you must take the most elementary of things as of themselves entitled to credence, instead of postulating them : which is useless, because some one else will adopt the contrary hypothesis. The mode arising from reciprocal inference is found whenever that which should be confirmatory of the thing requiring to be proved itself has to borrow credit from the latter, as, for example, if anyone seeking to establish the existence of pores on the ground that emanations take place should take this (the existence of pores) as proof that there are emanations. ^note

They would deny all demonstration, criterion, sign, cause, motion, the process of learning, coming into being, or that there is anything good or bad by nature. For all demonstration, say they, is constructed out of things either already proved or indemonstrable. If out of things already proved, those things too will require some demonstration, and so on ad infinitum ; if out of things indemonstrable, then, whether all or some or only a single one of the steps are the subject of doubt, the whole is indemonstrable. ^note If you think, they add, that there are some things which need no demonstration, yours must be a rare intellect, not to see that you must first have demonstration of the very fact that the things you refer to carry conviction in themselves. 9.11.91 Nor must we prove that the elements are four from the fact that the elements are four. Besides, if we discredit particular demonstrations, we cannot accept the generalization from them. And in order that we may know that an argument constitutes a demonstration, we require a criterion ; but again, in order that we may know that it is a criterion we require a demonstration ; hence both the one and the other are incomprehensible, since each is referred to the other. How then are we to grasp the things which are uncertain, seeing that we know no demonstration ? For what we wish to ascertain is not whether things appear to be such and such, but whether they are so in their essence.

They declared the dogmatic philosophers to be fools, observing that what is concluded ex hypothesi is properly described not as inquiry but assumption, and by reasoning of this kind one may even argue for impossibilities. As for those who think that