DISCRIMINATION AND COMPARISON. 523 



BBACTION-TIME AFTER DISCRIMINATION. 



The time required for discrimination has been made a 

 subject of experimental measurement. Wundt calls it Un- 

 terscheidungszeit. His subjects (whose simple reaction-time 

 - — see p. 85 ff. — had previously been determined) were re- 

 quired to make a movement, always the same, the instant 

 they discerned ivhich of two or more signals they received. 

 The exact time of the signal and that of the movement 

 were automatically registered by a galvanic chronoscope. 

 The particular signal to be received was unknown in ad- 

 vance, and the excess of time occupied by those reactions 

 in which its character had first to be discerned, over the 

 simple reaction-time, measured, according to Wundt, the 

 time required for the act of discrimination. It was found 

 longer when four different signals were irregularly used 

 than when only two were used. In the former case it 

 averaged, for three observers respectively (the signals be- 

 ing the sudden appearance of a black or of a white object), 



0.050 sec; 



0.047 " 



0.079 « 



ways a large number undiscriminated in consciousness, or (if one prefer 

 to call what is undiscriminated unconscious) in the soul. They are, how- 

 ever, not fused into a simple quality. When, on entering a room, we 

 receive sensations of odor and warmth together, without expressly attend- 

 ing to either, the two qualities of sensation are not, as it were, an entirely 

 new simple quality, which lirst at the moment in which attention analyti- 

 cally steps in chojiges into smell and warmth. ... In such cases we find 

 ourselves in presence of an iudetinable, uunamable total of feeling. And 

 when, after successfully analyzing this total, we call it back to memory, as 

 it was in its unanalyzed state, and compare it with the elements we have 

 found, the latter (as it seems to me) may be recognized as real parts con- 

 tained in the former, and the former seen to be their sum. So, for example, 

 when we clearly perceive that the content of our sensation of oil of pepper- 

 meut is partly a sensation of taste and partly one of temperature." (Ton- 

 ps3'chologie, 1. 107.) 



I should prefer to say that we perceive that objective fact, known to us 

 as the peppermint taste, to contain those other objective facts known as 

 aromatic or sapid quality, and coldness, respectively. No ground to sup- 

 pose that the vehicle of this last very complex perception has any identity 

 with the earlier psychosis— least of all is contained in it. 



