Full Idea
The two main anti-behaviourist intuitions are that mind and behaviour only relate contingently, and that for much mental life (thinking, emotion) the resulting behaviour seems unimportant.
Gist of Idea
Behaviour is too contingent and irrelevant to be the mind
Source
Georges Rey (Contemporary Philosophy of Mind [1997], 5.3)
Book Reference
Rey,Georges: 'Contemporary Philosophy of Mind' [Blackwell 1997], p.154
A Reaction
Attractive intuitions, but not unquestionable. Since no two states of mind are ever fully identical, we can never test whether the resulting behaviour arises contingently or necessarily. The second point underestimates the physicality of mental life.