CH. IV.] SUBSTITUTION OF NERVE-ACTIONS. 291 



actions, those movements which its external sensation would 

 have, or had, excited as its sentient actions (542, 543). Con- 

 quently, the vis nervosa of the external impression which induced 

 the emotion of sorrow, cannot excite as nerve- actions, the sen- 

 tient actions of the emotion. The same doctrine applies to 

 many other passions. 



566. Nevertheless, all passions are not excited so remotely, 

 and with the intervention of so many purely psychological con- 

 ceptions ; for there are some which, from their closer connection 

 with external sensations, are similar in their origin and de- 

 velopment to the instincts. With regard to this class, it must 

 often remain doubtful, whether they belong to the passions, or 

 to the instincts, or instinctive passions. Thus fear, alarm, and 

 terror (313, 318), which an external stimulus excites in us, 

 without an intervening series of irrelevant and purely psycho- 

 logical conceptions, is usually rather a form of the instinct of 

 self-preservation (299) : the anger and revenge of the dog rather 

 a modification of self-defence (326). The affection of many 

 animals for their ofPspring, which sometimes (as in monkeys), 

 appears to be a passion, is but a form of the instinct to tend 

 offspring (303) ; the frolicsomeness and cheerfulness of many 

 animals rather an iiistinctive passion for enjoyment (299). The 

 sentient actions of emotions of this class do not differ from 

 those of true instincts, except in being accompanied with the 

 sentient actions of some other conceptions, which the conceptive 

 force intermingles according to its own laws (297 — 304). Now, 

 since all these may be excited by the vis nervosa only (549, 552), 

 no repetition of proofs from observation (compare 553 — 562) is 

 necessary to demonstrate, that the same external impressions, 

 which, when felt, excite the sentient actions of these instinctive 

 passions, will also excite them by means of the vis nervosa only, 

 as nerve-actions. We will, however, analyse the emotion of 

 terror. In this, the external impressions cause a painful 

 external sensation; or such a sensation as induces a strong 

 sensational unpleasantness [Uulust] , because it excites a sudden 

 secondary sensational conception : as, for example, when an 

 individual hears a noise, he immediately imagines it to be 

 thunder, or, if he receives a blow, he conceives it to be given 

 by a robber. This disagreeable sensation changes the vital 

 movements contra-naturally, and violently (314, 318), and puts 



