SECT. XVII. 2. 1 1, OF MOTIONS. 149 



from regaining the loft aflbciation between the letters of it, but 

 which readily recurs when we have become carelefs about it. In 

 the fame manner, after having, for an hour laboured to recollect 

 the name of fome abfent perfon, it {hall feem, particularly after 

 fleep, to come into the mind as it were fpontaneoufly ; that is, 

 the word we are in fearch of, was joined to the preceding one 

 by aflbciation ; this aflbciation being diflevered, we endeavour 

 to recover it by volition ; this very adlion of the mind ftrikes 

 our attention more, than the faint link of aflbciation, and we 

 find it impoflible by this means to retrieve the loft word. After 

 fleep, when volition is entirely fufpended, the mind becomes 

 capable of perceiving the fainter link of aflbciation, and the word 

 is regained. 



On this circumftance depends the impediment of fpeech be- 

 fore mentioned ; the firft Syllable of a word is caufable by vo- 

 lition, but the remainder of it is in common converfation intro- 

 duced by its aflbciations with this firft fyllable acquired by long 

 habit. Hence when the mind of the ftammerer is vehemently 

 employed on fome idea of ambition of fhining, or fear of not 

 fucceeding, the aflbciations of the motions of the mufcles of ar- 

 ticulation with each other become diflevered by this greater ex- 

 ertion, and he endeavours in vain by voluntary efforts to rejoia 

 the broken aflbciation. For this purpofe he continues to re- 

 peat the firft fyllable, which is caufable by volition, and drives 

 in vain, by various diftortions of countenance, to produce the 

 next links, which are fubjecl; to aflbciation. See Clafs IV. 3.1.1. 



1 1. After our accomplished mufician has acquired great va- 

 riety of tunes and fongs, fo that fome of them begin to ceafe to 

 be eafily recollected, (he finds progreflive trains of muficai 

 notes more frequently forgotten, than thofe which are compo- 

 fed of reiterated circles, according with the eleventh preceding 

 article. 



12. To finiih our example with the preceding articles we 

 muft at length fuppofe, that our fair performer falls afleep over 

 her harpfichord j and thus by fufpenfion of volition, and the ex- 

 clufion of external ftimuli, (he diflevers the trains and circles of 

 her muficai exertions. 



III. i. Many of thefe circumftances of catenations of mo- 

 tions receive an eafy explanation from the four following confe- 

 quences to the feventh law of animal caufation in Sect. IV. 

 Thefe are, firit, that thofe fucceflions or combinations of animal 

 motions, whether they were united by caufation, aflbciation, or 

 catenation, which have been moft frequently repeated, acquire 

 the ftrongefi connexion. Secondly, that of thefe, thofe, which 

 have been lefs frequently mixed with other trains or tribes of 



motion, 



