SOURCE: "Pavlov's Theory of Conditioning," in the Psychological Review, Vol. 41, No. 2, March, 1934, pp. 199-206.

In the following essay, Guthrie offers a critique of Pavlov's theory of the conditioned reflex.

Pavlov's recent article, 'The Reply of a Physiologist to Psychologists,'¹ deals with two items printed some time ago in the Psychological Review, one by Lashley on 'Basic neural mechanisms in behavior,' and one by the writer, 'Conditioning as a principle of learning.' The issues raised by Pavlov deserve some further discussion because they are fundamental. My own article would have been justified if its only effect had been to persuade Pavlov to additional writing on the conditioned reflex, since by his laboratory experience he is undoubtedly its most competent exponent. However, on a number of points I remain quite unconvinced after reading his 'Reply.'

The first difference of opinion that he mentions concerns a very...