We now turn to one of the central problems of metaphysics, namely, the classical problem of universals. Ramsey writes on the subject in his first essay of some length, ‘Universals’, which was published in Mind in 1925, and he returns to the problem in an essay written for a symposium with H. W. B. Joseph and Richard Braithwaite, entitled ‘Universals and the “Method of Analysis”’.

Ramsey was interested in the problem of universals because his investigations of the foundations of mathematics more or less forced him to take this metaphysical problem seriously – which is more than one can say about most philosophers today, who try to escape it by not discussing it. However, one does not need to be dealing with the foundations of mathematics to see how central the problem of universals is. It can be approached in various ways.

If I lift my eyes for a moment from the yellow screen of the word-processor and look around my office, I will find a number of things which are yellow, too. On the bookshelves there are a number of yellow books; true, the shade of yellow varies, but nonetheless they are all yellow, and on the desk there are a couple of typical government-owned yellow pencils. These books, pencils and the yellow screen differ in a number of ways; yet they have a common characteristic – yellowness. The property these particulars all share is a universal.