2J.O PHILOSOPHY OF ZOOLOGY. 



powers, suffering no intermediate modifications, produce 

 actions characterised by great uniformity. 



In many cases, when an impression is produced upon us,, 

 which, as belonging to the instinctive powers, would have been 

 followed by action, the intellectual powers interpose their 

 controul, and the impression is surveyed before action is per- 

 mitted. But, as might have been expected, such action is 

 less varied, than when originally the result of an intellec- 

 tual process, but more irregular than in those cases in 

 which impression and action follow instantaneously. In 

 the one case, the action is modified, by the impression, in 

 the other, by the changes the impression has undergone by 

 thought. 



The powers to which we are now directing our attention, 

 are usually denominated, by the writers on the science of 

 mind, ACTIVE POWERS. To this appellation, however, 

 there are strong objections. There are other powers which 

 excite to action, inseparably connected with our constitu- 

 tion, which do not belong to this class. Some actions are 

 produced by irritability, of which we are not conscious. Ac- 

 tion is likewise produced by the information obtained by the 

 senses, through the medium of thought, or in consequence 

 of the ideas of reflection which spontaneously arise in the 

 mind. Hence the difference between the intellectual and in- 

 stinctive powers, is not so distinctly marked in the acts of 

 volition as in the manner in which these acts are excited. 

 It is with a view to avoid all ambiguity on the subject, that 

 we have ventured to substitute the term instinctive. 



Much confusion has arisen by the vague use of the 

 terms Instinct and Reason, and much vain speculation has 

 been indulged, in consequence of no distinct and definite 

 ideas being attached to them. No confusion, however, 

 could arise, were we to consider reason as expressing the 

 movements of our Intellectual powers, and instinct, those 



