34 SCIENCE PROGRESS 



Semon here takes as an instance of stimuli and imprint 

 actions affecting the nervous system of a dog 



"who has up till now never experienced ought 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 its tail between 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 con- 

 ditions of the living matter, so that the repetition of the imme- 

 diate 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, b (in this case the mere stooping to the 

 ground). I term the influences by which such changed reaction 

 are rendered possible * outcome-reactions,' and when such 

 influences assume the form of stimuli, ' outcome-stimuli.' " 



They are termed " outcome " (" ecphoria ") stimuli, 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.^ 



In the preface to his first edition (reprinted in the second) 

 Semon writes, after discussing the work of Hering and Haeckel: 



" The problem received a more detailed treatment in Samuel 

 Butler's book. Life and Habit, published in 1878. Though he 

 only made acquaintance with Hering's essay after this publica- 



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

 experience tells me that plain men in England have a special dread of such- 

 like, I have substituted "imprint" for " engram," "outcome" for "ecphoria'' ; for 

 the latter term I had thought of "efference," "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 Gra^cisms. 



