And suppose, I said, that I were asked by you what is the use or effect of medicine, which is this science of health, I should answer that medicine is of very great use in producing health, which, as you will admit, is an excellent effect. Granted. And if you were to ask me, what is the result or effect of architecture, which is the science of building, I should say houses, and so of other arts, which all have their different results. Now I want you, Critias, to answer a similar question about temperance, or wisdom, which, according to you, is the science of itself. Admitting this view, I ask of you, what good work, worthy of the name wise, does temperance or wisdom, which is the science of itself, effect? Answer me. That is not the true way of pursuing the enquiry, Socrates, he said; for wisdom is not like the other sciences, any more than they are like one another: but you proceed as if they were alike. For tell me, he said, what result is there of computation or geometry, in the same sense as a house is the result of building, or a garment of weaving, or any other work of any other art? Can you show me any such result of them? You cannot. That is true, I said; but still each of these sciences has a subject which is different from the science. I can show you that the art of computation has to do with odd and even numbers in their numerical relations to themselves and to each other. Is not that true? Yes, he said. And the odd and even numbers are not the same with the art of computation? They are not. The art of weighing, again, has to do with lighter and heavier; but the art of weighing is one thing, and the heavy and the light another. Do you admit that? Yes. Now, I want to know, what is that which is not wisdom, and of which wisdom is the science? You are just falling into the old error, Socrates, he said. You come asking in what wisdom or temperance differs from the other sciences, and then you try to discover some respect in which they are alike; but they are not, for all the other sciences are of something else, and not of themselves; wisdom alone is a science of other sciences, and of itself. And of this, as I believe, you are very well aware: and that you are only doing what you denied that you were doing just now, trying to refute me, instead of pursuing the argument. And what if I am? How can you think that I have any other motive in refuting you but what I should have in examining into myself? which motive would be just a fear of my unconsciously fancying that I knew something of which I was ignorant. And at this moment I pursue the argument chiefly for my own sake, and perhaps in some degree also for the sake of my other friends. For is not the discovery of things as they truly are, a good common to all mankind? Yes, certainly, Socrates, he said.