Full Idea
The acceptance of physicalism undercuts the other minds problem by equating experiences with events in the brain, which are publicly observable.
Gist of Idea
Physicalism undercuts the other mind problem, by equating experience with 'public' brain events
Source
A.J. Ayer (The Central Questions of Philosophy [1973], §VI.E)
Book Reference
Ayer,A.J.: 'The Central Questions of Philosophy' [Penguin 1976], p.132
A Reaction
It strikes me that if we could actually observe the operations of one another's brains, a great many of the problems of philosophy would never have appeared in the first place. Imagine a transparent skull and brain, with coloured waves moving through it.