CHAPTER XXVIIL 



BPEAKINO, READING, AND WRITING : AS MENTAL AND AS 

 PHYSIOLOGICAL PROCESSES. 



The views arrived at in the last chapter will be found 

 to harmonize well with what is known as to the mode in 

 which the faculty of Articulate Speech, together with 

 the superadded accomplishments of Reading and Writing, 

 are acquired. A preliminary consideration of these sub- 

 jects will, moreover, facilitate our comprehension of the 

 various defects in the power of Intellectual Expression 

 (whether by Speech or Writing) liable to be produced by 

 different kinds of Brain-disease : and the study of the latter 

 subject is most important for the psychologist. Its inves- 

 tigation has already revealed some very interesting facts as 

 to the order and precise relations of various mental pro- 

 cesses, as well as concerning their relationship to the func- 

 tional activity of particular tracts of Brain-tissue. We 

 are, indeed, in this manner afforded the nearest approach 

 that is possible to an experimental investigation of such 

 subjects. A close scrutiny of the necessary details will, 

 whilst furthering our knowledge, serve also (as a result 

 of this knowledge) to increase our chance of being able to 

 bring amelioration to the sufferers themselves. 



That Thought in all its higher modes cannot be carried 



on without the aid of Language is a proposition which 



will be almost universally admitted if we use the latter 



term in its broadest sense. For, as Thomson says,* 



* " Laws of Thought," 18G0, p. 27. 



