The Origin of the Cat’s Responses to Rats and Mice (Kuo — 1938)

Nicholas Porter
4 min readOct 30, 2022

A summary of Recent Experiments in Psychology — 1938 Edition

Is rat killing in cats “instinctive”?

The word “instinct” possesses so many unscientific connotations that it has fallen into disrepute among most psychologists. For this reason, a more satisfactory way to state the problem of these experiments is to say that their aim has been to discover to what extent rat killing is a native mode of behavior and to what extent it is acquired.

Cat and Mouse


Among the recent experiments which have dealt with the origin of the cat’s responses to rats and mice, the investigation of Kuo is one of the most significant, not only because it provides us with additional knowledge concerning the behavior of the cat, a favorite domestic animal, but also because it exemplifies sound scientific methods of handling the particular problem which it raises.

The meaning which will be attached to the words “native” and “acquired” in this article requires a brief explanation. A response may be regarded as native insofar as its nature is determined by genetic (inherited) factors. A native response is almost certain to appear when its proper stimulus is presented provided that the growth and development of the organism (1) have progressed under normal environmental circumstances, both before and after birth, and (2) have advanced far enough to make possible the reaction in question. Neither the experience nor that nature of native response is due primarily to modification through previous exposure to the stimulating situation (i.e due to learning).

3 Conditions (diagram)

The subjects of the experiment were split up among the following three conditions.

Experiment Design

Most people regard rat killing as instinctive because all the cats of their acquaintance do kill rats. Yet the universality of a response is no proof whatsoever that is is native. If all cats do kill rats under the normal living conditions of the species, then it is of course true that all cats must possess…