Chap. XIV. CONCLUDING REMARKS AND SUMMARY. 347 



CHAPTER XIV. 

 Concluding Bemarks and Summary. 



The three leading- principles which have determined the 

 chief movements of expression — Their inheritance — On 

 the part which the will and intention have played in 

 the accpiirement of various expressions — The instinctive 

 recognition of expression — The bearing - of our subject 

 on the specific unity of the races of man — On the suc- 

 cessive acquirement of various expressions by the pro- 

 genitors of man — The imporiance of expression — Con- 

 clusion. 



I hate now described, to the best of my ability, the 

 chief expressive actions in man, and in some few of 

 the lower animals. I have also attempted to explain 

 the origin or development of these actions through the 

 three principles given in the first chapter. The first 

 of these principles is, that movements which are service- 

 able in gratifying some desire, or in relieving some sensa- 

 tion, if often repeated, become so habitual that they are 

 performed, whether or not of any service, whenever the 

 same desire or sensation is felt, even in a very weak de- 

 gree. 



Our second principle is that of antithesis. The habit 

 of voluntarily performing opposite movements under 

 opposite impulses has become firmly established in us 

 by the practice of our whole lives. Hence, if certain 

 actions have been regularly performed, in accordance 

 with our first principle, under a certain frame of mind, 



