In a recent essay (1) Professor Taylor criticizes the criteria used by Rosenblueth, Wiener and Bigelow in 1943 (2) to distinguish purposeful from non-purposeful behavior. He also criticizes our definition of behavior, our concept of the vague as opposed to the general, our use of the word correlation, and our statement that a system may reach a final condition. Indeed, there seems to be little, if anything, in our paper to which he does not emphatically object.

He maintains that the notions of purpose and teleology are not only useless for the understanding of mechanical behavior, but wholly incongruous when applied to this behavior. He further affirms that our use of the term purpose “bears no similarity whatever to the meaning which is ordinarily attached to it.” He does not state, however, his own notions of purpose and teleology; and the meaning which he considers to be ordinarily attached to the term purpose. This omission weakens his criticism considerably.