or 'schema' or 'script' or whatever), then what 'causes' this act? (a physical feeling perhaps?) Clearly it must be preceded by another cognitive action, which must in turn be preceded by another and so on, in an infinite regress (always a sign that something has gone wrong with a theory). Guthrie's key point is that Tolman's explanation, which attempts to explain animal cognition, does not really explain anything at all. As a further example, we may take note of the following statement from The Concept of Mind: The main object of this chapter is to show that there are many activities which directly display qualities of mind, yet are neither themselves intellectual operations nor yet effects of intellectual operations. Intelligent practice is not a step-child of theory. On the contrary theorizing is one practice amongst others and is itself intelligently or stupidly conducted. In light of Ryle's critique, we may translate the statement by Emerson (still very much in common currency) into: "The ancestor of every action is an action." (This is so, since Ryle notes that, "theorizing is one practice amongst others.") - a reminder of Thomas Aquinas. Or we can go even further and argue that, according to Ryle: "The ancestor of every behavior is a behavior". As the use of the word 'behaviour' in the sentence above indicates, Ryle's regress arises from the Behaviorist tradition. Near the end of The Concept of Mind, Ryle states The Behaviorists’ methodological program has been of revolutionary importance to the program of psychology. But more, it has been one of the main sources of the philosophical suspicion that the two-worlds story is a myth.(The Concept of Mind, (1949), p. 328.) Ryle's brand of logical behaviorism is not to be confused with the radical behaviorism of B. F. Skinner, or the methodological behaviorism of John B. Watson. Alex Byrne noted that "Ryle was indeed, as he reportedly said, 'only one arm and one leg a behaviorist'." Cognitive scientists have Ryle's regress as a potential problem with their theories. A desideratum for those is a principled account of how the (potentially) infinite regress that emerges can be stopped. See also the homunculus fallacy. Response to Ryle's regress Immanuel Kant anticipated Ryle's Regress when he wrote in The Critique of Pure Reason the following: "But of reason one cannot say that before the state in which it determines the power of choice, another state