CH. II.] SENSATIONAL CONCEPTIONS. 47 



nothing therefore can be stated scientifically regarding them, 

 we will only consider those, of whose effects we know something. 



65. No animal thinks without feeling. Those which have 

 the smallest external senses, manifest the feeblest mental 

 power. Sensations precede all their other conceptions. How- 

 ever possible it may appear, that animals which have felt for a 

 time, can still continue to think after all sensation is lost, there 

 is no well-established example of this ; much less of an animal 

 possessing conceptions which it has never felt. Thus sensi- 

 bility [Empfindlichkeit] is the first stimulus of the conceptive 

 force in animals, and to this extent all their other conceptions 

 originate in their external sensations. Now, since external sen- 

 sations presuppose material ideas, produced by external im- 

 pressions on the nerves (34), it follows that the latter must 

 regulate all the mental phenomena, either directly through 

 external sensations, or indirectly. But since all conceptions 

 are connected with material ideas in the brain, the material 

 ideas of all conceptions must depend either directly or in- 

 directly, on external sensations in the brain, and on the external 

 impressions on the nerves. 



66. When, therefore, the matter is very closely considered, 

 we find that even the most spontaneous conceptions are oc- 

 casioned by external impressions on the nerves ; but this causa- 

 tion occurs in many so very indirectly, that the connection 

 becomes imperceptible ; in others, on the contrary, it is more 

 direct, often immediate, and this constitutes an important dis- 

 tinction in that class of conceptions which, in our arrangement 

 of external sensations, we have termed spontaneous (27) . It is 

 necessary, therefore, to bear this difference well in mind, and 

 not to adhere too closely, in a physiological inquiry, to the 

 ordinary psychological division of the conceptions and desires, 

 into the obscure, the indefinite, and the definite; a division 

 neither precise in itself, nor tending to the advancement of 

 physiology. When the mind is compelled to set in operation 

 and exercise its conceptive force by various external sensations, 

 each of which presents to it many sub-impressions of a single 

 object (53), it soon acquires a facility of conceiving some of these 

 sub-impressions spontaneously, although it can never attain to 

 the power to renew completely an external sensation, without the 

 aid of an external impression (35). Or this may be presented 



