The only clue to what man can do is what man has done

From The Idea of History by R.G. Collingwood. Page 9.

'The definition of history?' Every historian would agree, I think, that history is a kind of research or inquiry. What kind of inquiry it is I do not yet ask. The point is that generically it belongs to what we call the sciences: that is, the forms of thought whereby we ask questions and try to answer them. Science in general, it is important to realize, does not consist in collecting what we already know and arranging it in this or that kind of pattern. It consists in fastening upon something we do not know, and trying to discover it. Playing patience with things we already know may be a useful means towards this end, but it is not the end itself. It is at best only the means. It is scientifically valuable only in so far as the new arrangement gives us the answer to a question we have already decided to ask. That is why all science begins from the knowledge of our own ignorance: not our ignorance of everything, but our ignorance of some definite thing-the origin of parliament, the cause of cancer, the chemical composition of the sun, the way to make a pump work without muscular exertion on the part of a man or a horse or some other docile animal. Science is finding things out: and in that sense history is a science.

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Lastly, what is history for? This is perhaps a harder question than the others; a man who answers it will have to reflect rather more widely than a man who answers the three we have answered already. He must reflect not only on historical thinking but on other things as well, because to say that something is `for' something implies a distinction between A and B, where A is good for something and B is that for which something is good. But I will suggest an answer, and express the opinion that no historian would reject it, although the further questions to which it gives rise are numerous and difficult.

My answer is that history is `for' human self-knowledge. It is generally thought to be of importance to man that he should know himself: where knowing himself means knowing not his merely personal peculiarities, the things that distinguish him from other men, but his nature as man. Knowing yourself means knowing, first, what it is to be a man; secondly, knowing what it is to be the kind of man you are; and thirdly, knowing what it is to be the man you are and nobody else is. Knowing yourself means knowing what you can do; and since nobody knows what he can do until he tries, the only clue to what man can do is what man has done. The value of history, then, is that it teaches us what man has done and thus what man is.