Introduction xxxi 



Semon here takes the instance of stimulus and imprint 

 actions affecting the nervous system of a dog 



" who has up till now never experienced aught but kindness 

 from the Lord of Creation, and then one day that he is out 

 alone is pelted with stones by a boy. . . . Here he is affected 

 at once by two sets of stimuli: (i) the optic stimulus of 

 seeing the boy stoop for stones and throw them, and (2) the 

 skin stimulus of the pain felt when they hit him. Here both 

 stimuli leave their imprints ; and the organism is permanently 

 changed in relation to the recurrence of the stimuli. Hitherto 

 the sight of a human figure quickly stooping had produced no 

 constant special reaction. Now the reaction is constant, and 

 may remain so till death. . . . The dog tucks in its tail be- 

 tween its legs and takes flight, often with a howl [as of] pain." 

 " Here we gain on one side a deeper insight into 

 the imprint action of stimuli. It reposes on the lasting 

 change in the conditions of the living matter, so that the 

 repetition of the immediate or synchronous reaction to its 

 first stimulus (in this case the stooping of the boy, the flying 

 stones, and the pain on the ribs), no longer demands, as in 

 the original state of indifference, the full stimulus a, but may 

 be called forth by a partial or different stimulus, 6 (in this 

 case the mere stooping to the ground). I term the influences 

 by which such changed reaction are rendered possible, ' out- 

 come-reactions,' and when such influences assume the form of 

 stimuli, ' outcome-stimuli.' " 



They are termed " outcome " (" ecphoria ") stimuh, 

 because the author regards them and would have us regard 

 them as the outcome, manifestation, or efference of an 

 imprint of a previous stimulus. We have noted that the 

 imprint is equivalent to the changed " physiological 

 state " of Jennings. Again, the capacity for gaining 

 imprints and revealing them by outcomes favourable to 

 the individual is the " circular reaction " of Baldwin, but 

 Semon gives no reference to either author.^ 



1 Semon's technical terms are exclusively taken from the Greek, 

 but as experience tells that plain men in England have a special 

 dread of suchlike, I have substituted "imprint" for " engram," 

 "outcome" for "ecphoria"; for the latter term I had thought of 

 "eiference," "manifestation," etc., but decided on what looked 

 more homely, and at the same time was quite distinctive enough to 

 avoid that confusion which Semon has dodged with his Graecisms. 



