ON THE PSYCHO-PHYSICAL VIEW OF NATURE. 541 



Emotions in Man and Animals ' a year after. Tiiese 

 \vritings did more than any others to impress upon 

 jihilosophers the genetic or historical view, the existence 

 of an unln'oken chain or transititjn from the lower to the 

 liigher and the liigliest forms of animal structures, and 

 culminated in the well-known expression of Darwin, that 

 ' in a series of forms graduating insensibly from some 

 ape-like creature to man as he now exists, it would he 

 impossible to fix at any definite jjoint when the term 

 * man ' ought to be used." ^ This dictum has been the 

 theme on which endless variations have been played 

 down to the present day — Prof. Ernest Haeckel's address 

 to tlie Congress of Zoology at Cambridge in 1898 being 

 the latest summary of tlie physical aspect of the proldem. 

 But the problem has also a psycho-physical side, and this 

 aspect is concentrated in the problem of language. Even 

 those philologists who, like August Schleicher and I\lax 

 Miiller, look upon the science of language as a natural 

 science, bring in at this point tlie accumulated and 

 weighty evidence of the historical, psychological, ami 

 })hilosophical researches into the growth and development 

 of human speech and human thought, as absolutely 

 negativing the possibility of a gradual transition from the 4S. 



Tlie dividing 



brute to the Innnan creation. To the latter, language, Hne between 



° ° man and 



which he considers to l^e the union of definite concepts '^™^'^- 

 with definite names, is the liubicon which cannot be 

 crossed," tlie chasm which (li\i<les that ]K)rtion of the 



^ 'Descent of Man,' 1st ed., vol. 

 i. p. 23.'^. 



- See :^Iiix Miiller, ' The Science 

 of Thouf^lit,' piixxim, notably chap. 

 iv. p. 177, where he (juotes and 

 maintains his dictum of 1861 ( ' Lec- 



tures on the Science of Language,' 

 vol. i. p. 403) : " Language is our 

 Rubicon, and no biute will dare to 

 cross it." Referring to Schleicher, 

 he says (p. 164) : " Professor 

 Schleicher, though an enthusiastic 



