It's difficult to be rigorous about whether a machine really 'knows', 'thinks', etc., because we're hard put to define these things. We understand human mental processes only slightly better than a fish understands swimming.
— John McCarthy, The Little Thoughts of Thinking Machines (1983)
Source: http://www-formal.stanford.edu/jmc/little.html
From a December 1983 Psychology Today article, reprinted in Formalizing Common Sense (1990).
Topics: artificial intelligence