DISCRIMINATION AND COMPARISON. 517 



an existing part of tlie sum of the sensations excited in us. We will 

 say, then, that the sensation is perceived analytically. The two cases 

 must be carefully distinguished from each other." * 



By tlie sensation being perceived synthetically, Helm- 

 lioltz means that it is not discriminated at all, but only felt 

 in a mass with other simultaneous sensations. That it is 

 felt there he thinks is proved by the fact that our judg- 

 ment of the total will change if anything occurs to alter 

 the outer cause of the sensation. t The following pages 

 from an earlier edition show what the concrete cases of 

 synthetic perception and what those of analytic perception 

 are wont to be : 



" In the use of our senses, practice and experience play a much larger 

 part than we ordinarily suppose. Our sensations are in the first in- 

 stance important only in so far as they enable us to judge rightly of 

 the world about us ; and our practice in discriminating between them 

 usually goes only just far enough to meet this end. We are, however, 

 too much disposed to think that we must be immediately conscious of 

 every ingi'edient of our sensations. This natural prejudice is duo to 

 the fact that we are indeed conscious, immediately and withoirt effort, 

 of everything in our sensations which has a bearing upon those practi- 

 cal purposes, for the sake of which we wish to know the outer world. 

 Daily and hourly, during our whole life, we keep our senses in training 

 for this end exclusively, and for its sake our experiences are accumu- 

 lated. But even within the sphere of these sensations, which do corre- 

 spond to outer things, training and practice make themselves felt. It is 

 well known how much finer and quicker the painter is in discriminating 

 colors and illuminations than one whose eye is not trained in these 

 matters ; how the musician and the musical-instrument maker perceive 

 with ease and certainty differences of pitch and tone which for the ear 

 of the layman do not exist ; and how even in the inferior realms of 

 cookery and wine-judging it takes a long habit of compai'ing to make a 

 master. But more strikingly still is seen the effect of practice when 

 we pass to sensations which depend only on inner conditions of our 

 organs, and which, not corresponding at all to outer things or to their 

 effects upon us, are therefore of no value in giving us information about 

 the outer world. The physiology of the sense-organs has, in recent 

 times, made us acquainted with a number of such phenomena, discov- 

 ered partly in consequence of theoretic speculations and questionings, 

 partly by individuals, like Goethe and Purkinje, specially endowed by 

 nature with talent for this sort of observation. These so-called subjec- 



* Sensations of Tone, 3d English Edition, p. 62. 



•)• Compare as to this, however, what I said above, Chapter V, pp 

 172-176. 



