May 1, 1914] 



SCIENCE 



629 



havior), and, third, a law of behavior for 

 the particular organism in question. In 

 effect, what I did with the dancing mouse 

 might be done with human subjects, should 

 it seem desirable to gain definite knowl- 

 edge of this aspect of habit-formation. As 

 it happens, precisely the kind of kno^Vledge 

 of human behavior which such experi- 

 mental methods yield is necessary, if we 

 are ever to have a thoroughgoing science of 

 human behavior which will enable us to 

 deal with our fellows effectively. 



Another illustration may be taken from 

 the study of imitative activity. It is gener- 

 ally recognized that imitation may be 

 studied experimentally in any organism. 

 But up to the present most observations of 

 this group of phenomena have been casual, 

 and our opinions concerning the impor- 

 tance of imitation in any organism are 

 quite likely to be based upon insufficient or 

 inaccurate information. With sparrows, 

 canaries, mice, rats, cats, dogs, monkeys, 

 experiments have been made to determine 

 the nature and extent of imitative reaction, 

 and there is no obvious reason why the 

 methods of the behaviorists should not be 

 adapted to the study of the imitative tend- 

 ency in human beings. 



In order to exhibit, in its general fea- 

 tures, a method of studying imitation ex- 

 perimentally, we shall consider investiga- 

 tions of this aspect of behavior in monkeys.^ 

 The observer, first of all, seeks for a num- 

 ber of acts or series of acts which his ani- 

 mals either can not learn to perform of their 

 own initiative or learn with extreme diiifi- 

 culty. Such acts are most readily dis- 

 covered in connection with artificially 

 arranged situations, as, for example, in 



5 Haggerty, M. E., ' ' Imitation in Monkeys, ' ' 

 Journal of Comparative Neurology and Psychol- 

 ogy, 1909, Vol. 19, p. 337; Watson, B., "Imita- 

 tion in Monkeys," Psychological Bulletin, 1908, 

 Vol. 5, p. 169. 



connection with puzzle or problem boxes 

 and similar experimental devices. He then 

 teaches one animal to perform an act and 

 thereafter, under definitely describable and 

 constant conditions, he permits another 

 animal to observe the behavior of the first. 

 Any tendency for the second animal to 

 imitate the first, or to modify its behavior 

 in accordance with the activities of the first, 

 is noted. Thus, by repetition after repeti- 

 tion of this sort of experiment, the observer 

 strives to get definite knowledge of the 

 nature and extent to which the behavior of 

 one animal influences that of its fellows. It 

 is, of course, necessary in such an experi- 

 ment to work out a method carefully and 

 to make all observations under carefully 

 controlled conditions. It is necessary, also, 

 to measure as precisely as possible several 

 aspects of the behavior of the observing 

 individual, and thus to depend not upon 

 general impressions, but upon records which 

 can not be influenced by any bias on the 

 part of the experimenter. 



Such experimental studies as those of 

 Watson and Haggerty have proved that 

 certain monkeys imitate much less gener- 

 ally than is commonly supposed. And fur- 

 ther, that they imitate seldom, if ever, in 

 the purposive manner in which man imi- 

 tates. It seems that although they influence 

 one another markedly in their behavior, 

 this influence is chiefly a matter of the 

 directing of attention. The imitation of 

 means or of ends in a voluntary and wholly 

 conscious manner rarely appears among 

 the mammals below man. 



An illustration from actual experimental 

 work which clearly indicates the need of 

 analyzing behavior complexes and of deal- 

 ing quantitatively with simple bits of be- 

 havior is furnished by some recent work 

 which the writer has done with rats. It 

 was his task to try to discover the modes of 

 heredity of savageness and wildness in rats. 



