Full Idea
Nothing mental is presupposed in the fact that Edinburgh is north of London, but this involves the universal 'north of', so we must admit that relations are not dependent upon thought, but belong to the independent world which thought apprehends.
Gist of Idea
That Edinburgh is north of London is a non-mental fact, so relations are independent universals
Source
Bertrand Russell (Problems of Philosophy [1912], Ch. 9)
Book Reference
Russell,Bertrand: 'The Problems of Philosophy' [OUP 1995], p.56
A Reaction
We cannot deny that Edinburgh being north of London is independent of our minds, but we might deny that 'north of' is a universal. 'North' is clearly a human convention, but 'nearer a pole' isn't. Distances exist in space, rather than as relations.