Italy to England?

Russell began his published work in 1896 with German Social Democracy, a study in politics that was an early indication of a lifelong interest in political and social theory. In 1896 he taught German social democracy at the London School of Economics.^[105] He was a member of the Coefficients dining club of social reformers set up in 1902 by the Fabian campaigners Sidney and Beatrice Webb.^[106]

He now started an intensive study of the foundations of mathematics at Trinity. In 1898 he wrote An Essay on the Foundations of Geometry which discussed the Cayley–Klein metrics used for non-Euclidean geometry.^[107] He attended the International Congress of Philosophy in Paris in 1900 where he met Giuseppe Peano and Alessandro Padoa. The Italians had responded to Georg Cantor, making a science of set theory; they gave Russell their literature including the Formulario mathematico. Russell was impressed by the precision of Peano's arguments at the Congress, read the literature upon returning to England, and came upon Russell's paradox. In 1903 he published The Principles of Mathematics, a work on foundations of mathematics. It advanced a thesis of logicism, that mathematics and logic are one and the same.^[108]