Perhaps philosophy is more like this: still keep your butt and your dealer, but no wine; rather take an assortment of cereals—wheat on top, then beans, then barley, and, beneath the barley, lentils, then chickpeas, and other kinds of seeds as well. You come in wishing to buy some of the cereals. He has taken out a pinch of the wheat from where the wheat was and has given you a sample in your hand to examine. Now could you say by looking at that sample whether the peas were pure, the lentils tender, and the beans not completely empty?

Not at all.

Then neither could you learn the nature of all philosophy from the first thing someone says. For it is not really one substance like the wine to which you compare it, claiming that it is like the sample. No, we have seen that there is variation in it, for which a cursory examination will not do. If you buy bad wine you risk a couple of pence, but to rot in the common herd oneself, as you said in the beginning, is very serious. Besides, to insist on drinking the whole butt in order to buy half a pint is to cause loss to the wine-merchant with your unbelieving tasting. But in philosophy there would be no such loss. No, however much you drink, the butt is just as full and the wine-merchant will not suffer loss. For, in the words of the proverb, the more you draw the fuller it becomes. The case is the reverse of the butt of the Danaïdes that would not hold what was put into it but let it run away at once. Take some away from philosophy, however, and what is left increases.