We are bits of stellar matter that got cold by accident, bits of a star gone wrong. - Arthur Eddington

Phys. I know that it is often a help to represent pressure and volume as height and width on paper; and so geometry may have applications to the theory of gases. But is it not going rather far to say that geometry can deal directly with these things and is not necessarily concerned with lengths in space? Math. No. Geometry is nowadays largely analytical, so that in form as well as in effect, it deals with variables of an unknown nature. … It is literally true that I do not want to know the significance of the variables x, y, z, t that I am discussing. … Phys. Yours is a strange subject. You told us at the beginning that you are not concerned as to whether your propositions are true, and now you tell us you do not even care to know what you are talking about.
Math. That is an excellent description of Pure Mathematics, which has already been given by an eminent mathematician <nowiki>[</nowiki>Bertrand Russell<nowiki>]</nowiki>.

Never trust an experimental result until it has been confirmed by theory

The essential difference, which we meet in entering the realm of spirit and mind, seems to hang round the word "Ought."