Plato, Protagoras

[356a] unworthy to conquer. What unworthiness can there be in pleasure as against pain, save an excess or defect of one compared with the other? That is, when one becomes greater and the other smaller, or when there are more on one side and fewer on the other, or here a greater degree and there a less. For if you should say: But, Socrates, the immediately pleasant differs widely from the subsequently pleasant or painful, I should reply: Do they differ in anything but pleasure and pain? [356b] That is the only distinction. Like a practised weigher, put pleasant things and painful in the scales, and with them the nearness and the remoteness, and tell me which count for more. For if you weigh pleasant things against pleasant, the greater and the more are always to be preferred: if painful against painful, then always the fewer and smaller. If you weigh pleasant against painful, and find that the painful are outbalanced by the pleasant—whether the near by the remote or the remote by the near—you must take that course of action to which the pleasant are attached; [356c] but not that course if the pleasant are outweighed by the painful. Can the case be otherwise, I should ask, than thus, my friends? I am certain they could state no alternative.

To this he too assented.

Since that is the case, then, I shall say, please answer me this: Does not the same size appear larger to your sight when near, and smaller when distant? They will admit this. And it is the same with thickness and number? And sounds of equal strength are greater when near, and smaller when distant? [356d] They would agree to this. Now if our welfare consisted in doing and choosing things of large dimensions, and avoiding and not doing those of small, what would be our salvation in life? Would it be the art of measurement, or the power of appearance? Is it not the latter that leads us astray, as we saw, and many a time causes us to take things topsy-turvy and to have to change our minds both in our conduct and in our choice of great or small? Whereas the art of measurement would have made this appearance ineffective, [356e] and by showing us the truth would have brought our soul into the repose of abiding by the truth, and so would have saved our life. Would men acknowledge, in view of all this, that the art which saves our life is measurement, or some other?

It is measurement, he agreed.

Well now, if the saving of our life depended on the choice of odd or even, and on knowing when to make a right choice of the greater and when of the less—taking each by itself or comparing it with the other, and whether near