If you thought that the founders of the Artificial Intelligence movement were the first to think that intelligence was just the product of computation, think again:
When man reasoneth, he does nothing else but conceive a sum total, from addition of parcels….For reason, in this sense, is nothing but reckoning
Thomas Hobbes, Leviathan, Chapter 5 ‘Of Reason and Science’
Mind Hacks 
John Haugeland, in his book Artificial Intelligence: The Very Idea, uses this famous quote in his discussion of Hobbes as an early computationalist.
Haugeland’s book is one of the best in the genre of “philosophy of AI”. It is written in a very clear and simple style, which masks the profundity of the ideas being presented.
This, for me, sums up the problem of modern psychiatry:
“5.8.1 The first cause of absurd conclusions I ascribe to the want of method; in that they begin not their ratiocination from definitions; that is, from settled significations of their words..”
http://thelastpsychiatrist.com
I’ve always been reminded of “you will know them by their fruit” when I think of functionalistm.
Mathew 7
15 “Beware of false prophets, who come to you in sheep’s clothing, but inwardly they are ravenous wolves. 16You will know them by their fruits. Do men gather grapes from thornbushes or figs from thistles? 17Even so, every good tree bears good fruit, but a bad tree bears bad fruit. 18A good tree cannot bear bad fruit, nor can a bad tree bear good fruit.
19Every tree that does not bear good fruit is cut down and thrown into the fire. 20Therefore by their fruits you will know them.