The project of deducing mathematics from logic appealed to him, and to my great joy he agreed to collaborate.

I saw that methods analogous to his would clarify the logic of relations, and I was led to the definitions of cardinal, ordinal, rational, and real numbers which are given in The Principles of Mathematics. I n 1900 we went together to the International Congress of Philosophy in Paris, where I was impressed by Peano. He was always quite exceptionally kind, and passed by gradual stages from a teacher to a friend. He was one of tde examiners when I was a candidate first for a scholarship and then for a fellowship. Whitehead was already a lecturer at Trinity when I was a freshman : in mv first term I attended his lectures on Statics. As no one except myself now knows what were our respective shares, I will try to state the facts as nearly as I can remember them. THEREis in some quarters a tendency to suppose that Whitehead's part in our joint work was less than in fact it was. PSYCHOLOGY A N D PHILOSOPHY I.-WHITEHEAD A N D PRINCIPIA For more information regarding JSTOR, please contact JSTOR is an independent not-for-profit organization dedicated to and preserving a digital archive of scholarly journals.

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