ON THE PSYCHO-PHYSICAL VIEW OF NATUKE. 539 



ments of speech. Simultaneously the discovery by Broca, 

 in 1861, of the speech centre in the brain marked an 

 epoch on the physiological side. 1 A new science, called 

 Phonetics or Phonology, has sprung up, and is now 47. 



Phonetics. 



universally admitted to have created the modern science 

 of language. 2 In addition to this physiological and 

 physical basis, the superstructure of the science of 



1 This localisation places the 

 .speech centre in "a very circum- 

 scribed portion of the cerebral 

 hemispheres, and more especially 

 of the left. This portion is situate 

 on the upper edge of the Sylvian 

 Fissure, opposite the island of 

 Reil, and occupies the posterior 

 half, probably only the posterior 

 third, of the third frontal convolu- 

 tion" (Broca, 'Bulletins de la 

 Socie'te anatomique,' 1861). The 

 discovery resulted from the ex- 

 amination of the brain of patients 

 who had been afflicted with "aph- 

 asia, " which is accompanied with 

 "a lesion of the posterior half of 

 the third, left or right, frontal con- 

 volution, nearly always nineteen 

 times out of twenty of the left 

 convolution." The phenomenon 

 of aphasia has ever since been 

 one of the great psycho-physical 

 problems bringing together the 

 most refined and intricate physi- 

 ological, psychological, and linguis- 

 tic analyses. To begin with, we 

 have to distinguish motor aphasia 

 and sensory aphasia. " Our know- 

 ledge of this disease has had three 

 stages : we may talk of the period 

 of Broca, the period of Wernicke, 

 and the period of Charcot. Wer- 

 nicke (1874) was the first to dis- 

 criminate those cases in which the 

 patient cannot even understand 

 speech from those in which he can 

 understand, only not talk ; and to 

 ascribe the former condition to 

 lesion of the temporal lobe. The 



condition in question is word-deaf- 

 ness, and the disease is auditory 

 aphasia. . . . The minuter analy- 

 sis of the facts in the light of 

 individual differences constitute 

 Charcot's contribution towards 

 clearing up the subject " (James, 

 'Principles of Psychology,' vol. i. 

 p. 54). 



2 In the modern science of lan- 

 guage we have one among the 

 many cases where a historical or 

 philosophical science is becoming 

 an exact science by attaching itself 

 to physics and physiology. On 

 the other side we have the great 

 movement initiated by Darwin in 

 the purely natural sciences, which, 

 as was shown above, relies on the 

 historical collection of facts and 

 the judicious critical sifting of evi- 

 dence. "It is phonology," says 

 Prof. Sayce ('Introduction to the 

 Science of Language,' 2 vols., 1880, 

 chap, iv.), "which has created the 

 modern science of language, and 

 phonology may therefore be forgiven 

 if it has claimed more than right- 

 fully belongs to it or forgotten that 

 it is but one side and one branch 

 of the master science itself. . . . 

 It is when we pass from the out- 

 ward vesture of speech to the 

 meaning which it clothes, that the 

 science of language becomes a his- 

 torical one. The inner meaning 

 of speech is the reflection of the 

 human mind, and the development 

 of the human mind must be stud- 

 ied historically." 



