270 APPENDIX. [No. XVII.A. 



But, after the remarkable kindness with whioli the work has been 

 received in this country by my friends and the public, I feel that it would 

 be a want of courtesy, if not an act of ingratitude, to allow further 

 remarks upon the same subject, however unimportant they may be, to 

 appear in a foreign country before they were issued in the English language. 



I apprehend that the time is fast approaching, when no other 

 system of mental science will be acknowledged but that which is based 

 upon physical laws and the structure of the brain ; and if my researches 

 shall be found hereafter to have contributed to the development of true 

 philosophy, I shall indeed feel more than amply rewarded for the hours of 

 anxious but delightful labour spent in its development. 



7, riNSBTJBY ClECtrS, 



Sept. 18th, 1849. 



Knowledge of the external World. 



1. Our ideas of the external world ai-ise, primarily, from an action 

 upon the ultimate nervous fibres of the organs of sensation, by the specific 

 stimulus competent to excite each organ of sensation respectively. 



2. Each primitive nervous fibril is called a unit; the repetition of 

 units. Number. 



3. That which is competent to act upon these nervous fibrils is called 

 Matter. 



4. Whenever matter undergoes any change which renders it appre- 

 ciable to our senses, it is said to evince Force. 



5. The definite combination of nervous fibres excited to action, deter- 

 mines the character of the idea presented to the mind, such as form, posi- 

 tion, magnitude. 



6. Each combination may be expressed by a word or cypher, and 

 forms a definite image. The use of words is called Language. 



7. The sum total of all the possible combinations of the ultimate 

 nervous fibrils, excited to action, comprises all the possible images which 

 can be represented to the mind. 



8. Inasmuch as the possible combination of all the nervous fibrils is 

 immensely numerous, so are the images which may be reflected in the 

 mind immensely numerous. 



Senses. 



9. An idea is represented to the mind, when any one or more of the 

 filaments of either specific organ of sensation is excited without reference 

 to the definite image thereby produced. 



10. This solitary idea, derived from the filaments of the eye, is termed 

 Vision ; of the ear. Hearing ; of the nose. Smelling ; of the palate. Tasting ; 

 of the skin. Feeling ; and probably, from the nei-ves communicatino- the 

 changes occurring in our own body. Personality. 



Combination of Senses. 



11. The perfect knowledge of any object is obtained by impressions 

 received by the sum of the organs of sensation. 



12. But as matter may exist without exciting all the organs of sensa- 

 tion at one time, we determine the combination of senses which has 



' concurred to give us the knowledge of any external object. 



