Full Idea
On the view that we are discussing, I must regard other people as metaphysical objects; for it is assumed that their experiences are completely inaccessible to my observation.
Gist of Idea
Other minds are 'metaphysical' objects, because I can never observe their experiences
Source
A.J. Ayer (Language,Truth and Logic [1936], Ch.7)
Book Reference
Ayer,A.J.: 'Language, Truth and Logic' [Penguin 1974], p.170
A Reaction
'Metaphysical' is here a dirty word. This is the strictly empirical view of other minds, which pushes Ayer towards behaviourism on this subject. He should have asked about the 'best explanation' of the behaviour of others'.