45

O.13

an arbitrary hypothesis, in the sense in which the initial hypotheses of pure mathematics are said to be arbitrary; that is, there is no reason to think that they are existentially realized, perhaps the reverse.) Let him contemplate them in all ways, regardless of all maxims that seek to set up bars across the path of inquiry. For experience can teach him, as I trust it has me, effectually, that nothing can be more pernicious. In my youth, I used to read from the great "authorities" of those days such saws as that, "one science should not borrow the methods of another"; "the only really scientific part of astronomy must