[2] Other philosophers with sympathies for behaviorism included C. G. Hempel, Ludwig Wittgenstein, and W. V. O. Quine (1960).
[2][3] A more moderate form of analytical behaviorism was put forward by the Oxford philosopher Gilbert Ryle in his book The Concept of Mind (1949).
For example, a dualist would take 'Finbarr is in pain' to refer to a private, non-physical mental state within Finbarr's mind.
But a behaviourist would say that 'Finbarr is in pain' simply refers to Finbarr's behaviour, or his disposition to behave in a certain way.
To introduce his behaviourism, Ryle proposes his great criticism of Cartesianism: that it performs a category mistake.
Ryle believes that mind-body dualism mistakenly puts the mind in the category of a 'thing', a non-physical entity that exists, driving our actions.
It has also been argued that behaviourist analysis of mental state terms can never truly be adequately completed.
This is due, in large part, to the fact that mental states are multiply realisable in behaviour.
Another issue, on top of multiple realisability, is the fact that behavioural analysis of mental states becomes circular.
For example, my mental state of wanting to drink my glass of water might not be manifested in behaviour (ie.
I just know, through introspection, which would show that a purely behavioural analysis of mental states is inadequate.
In a similar way, it was thought by the Vienna Circle that the phenomena of human mental states such as feelings, perceptions, imaginations etc.