The question what presuppositions underlie the 'physics' or natural science of a certain people at a certain time is a purely historical question as … - R. G. Collingwood

It is only when a man's historical consciousness has reached a certain point of maturity that he realizes how very different have been the ways in which different sets of people have thought. When a man first begins looking into absolute presuppositions it is likely that he will begin by looking into those which are made in his own time by his own countrymen, or at any rate by persons belonging to some group of which he is a member. This, of course, is already an historical inquiry. But various prejudices current at various times which I will not here enumerate have tended to deceive such inquirers into thinking that the conclusions they have reached will hold good far beyond the limits of that group and that time. They may even imagine that an absolute presupposition discovered within these limits can be more or less safely ascribed to all human beings everywhere and always.

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

Time, as succession of past, present and future, really has its being totum simul for the thought of a spectator, and this justifies its ‘spatialized’ presentation as a line of which we can see the whole at once.