!H. I.] RELATIONS OF IMPRESSIONS. 217 



)roduced acts in the same way as a volition^ and the animal is 

 jxcited to raise itself up. Whilst the muscles are contracted 

 this end^ their nerves have an external impression commu- 

 licated to them by the movement, which irritates them and 

 rther muscles to new movements_, so that the animal either 

 )laces itself upright, or balances itself, or turns round, retreats, 

 lakes a spring, swims, &c., according as the irritation of the 

 jpinal cord has excited the first movement. 



402. To determine more definitely the relationship which the 

 two kinds of impressions bear to external and internal sensations, 

 re will still further consider their relations. An external im- 

 )ression is necessarily required for all external sensations (35), 

 id, consequently, constitutes a portion of them, but only in so far 

 it is felt, for the entire external sensation is in the mind — is 

 conception (34) . Taken alone, it is a portion of the material 

 external sensation, but only in so far as it forms therewith a 

 material idea at the origin of the nerves which have received 

 it (34). Popularly, and indeed in books also, external sensation 

 generally, and in its widest signification, is termed feeling 

 [Gefiihl], and attributed to the five senses, for it is said that 

 the eye feels the rays of light, the ear feels the undulations of 

 the atmosphere, &c. It is also customary to apply the term 

 sensation and feeling to animal bodies, for it is said that the 

 hand, the flesh, a nerve, feels and has sensation. According 

 to this established signification of the terms, it may be said 

 that the external impression is an element in feeling (the 

 material external sensation), and since it produces the same 

 phenomena, whether it reaches the brain to form material 

 ideas in it or not, the name is derived from a part, and the 

 external impression thus becomes to be designated the external 

 feeling [Gefiihl] of the nerves (32). In this way, the external 

 impression and the material external sensation in the brain 

 may be distinguished by convenient terms, both of which are 

 figurative, the latter being termed sensation [Empfindung], the 

 sentiment of Buff'on ; the former, the external feeling of the 

 nerves — sensation of Buff'on. Thus it is said, that the 

 tongue, the hand, the ear, have sensation, whilst a decapitated 

 animal, or an excised heart, or portion of intestine, so long as 

 it is excited to motion by a purely external impression, is said 

 to have feeling left in it, or that the acephalous embryos, which. 



