"32 Additional Notes. 



pain or pleasure, and consequent volition to examine the object of it, 

 as explained in Zoonomia, Vol. I. Sect. XVIII. 17, and which never 

 affects us hi sleep. In our waking hours whenever an idea of imagi- 

 nation occurs, which is incongruous to our former experience, Are 

 feel another kind of surprise, and instantly dissever the train of ima- 

 gination by the power of volition, and compare the incongruous idea 

 with our previous knowledge of nature, and reject it by an act of rea- 

 soning, of which we are unconscious, termed in Zoonomia, "Intuitive 

 Analogy," Vol. I. Sect. XVII. 7. 



The novelty of any idea may be considered as affecting us with 

 another kind of surprise, or incongruity, as it differs from the usual 

 train of our ideas, and forms a new link in this perpetual chain; 

 which, as it thus differs from the ordinary course of nature, we 

 instantly examine by the voluntary efforts of intuitive analogy; or by 

 reasoning, which we attend to; and compare it with the usual appear- 

 ances of nature. 



These ideas which affect us with surprise, or incongruity, or 

 novelty, are attended with painful or pleasurable sensation; Avhich 

 we mentioned before as intermixing with all catenations of animal 

 actions, and contributing to strengthen their perpetual and energetic 

 production ; and also exciting in some degree the power of volition, 

 which also intermixes with the links of the chain of animal actions, 

 and contributes to produce it. 



Now by frequent repetition the surprise, incongruity, or novelty 

 ceases; and, in consequence, the pleasure or pain which accompanied 

 it, and also the degree of volition which was excited by that sensation 

 of pain or pleasure; and thus the sensorial power of sensation and of 

 volition are subducted from the catenation of vital actions, and they 

 are in consequence produced much weaker, and at length cease 

 entirely. Whence we learn why contagious matters induce their 

 effects on the circulation but once ; and wlvy, in process of time, the 

 vital movements are performed with less energy, and at length cease ; 

 whence the debilities of age, and consequent death. 



