Full Idea
When we assert 'p or q' we are in a state which is derivative from two previous states, and we express this state, not something about the world.
Gist of Idea
'Or' expresses a mental state, not something about the world
Source
Bertrand Russell (An Inquiry into Meaning and Truth [1940], 5)
Book Reference
Russell,Bertrand: 'An Inquiry into Meaning and Truth' [Penguin 1967], p.81
A Reaction
His example: at a junction this road or that road goes to Oxford, but the world only contains the roads, not some state of 'this or that road'. He doesn't deny that in one sense 'p or q' tells you something about the world.