Chap. II. 
MENTAL POWERS. 
37 
an instinctive dread of serpents, and probably of other 
dangerous animals. 
The fewness and the comparative simplicity of the 
instincts in the higher animals are remarkable in con- 
trast with those of the lower animals. Cuvier main- 
tained that instinct and intelligence stand in an inverse 
ratio to each other; and some have thought that the 
intellectual faculties of the higher animals have been 
gradually developed from their instincts. But Pouchet, 
in an interesting essay , 2 has shewn that no such inverse 
ratio really exists. Those insects which possess the most 
wonderful instincts are certainly the most intelligent. 
In the vertebrate series, the least intelligent members, 
namely fishes and amphibians, do not possess complex 
instincts ; and amongst mammals the animal most re- 
markable for its instincts, namely the beaver, is highly 
intelligent, as will be admitted by every one who has 
read Mr. Morgan’s excellent account of this animal . 3 
Although the first dawnings of intelligence, accord- 
ing to Mr. Herbert Spencer , 4 have been developed 
through the multiplication and co-ordination of reflex 
actions, and although many of the simpler instincts 
graduate into actions of this kind and can hardly be 
distinguished from them, as in the case of young animals 
sucking, yet the more complex instincts seem to have 
originated independently of intelligence. I am, how- 
ever, far from wishing to deny that instinctive actions 
may lose their fixed and untaught character, and be 
replaced by others performed by the aid of the free will. 
On the other hand, some intelligent actions — -as wdien 
birds on oceanic islands first learn to avoid man — after 
2 ‘L’lnstinct chez les Insectes.’ 1 Revue des Deux Moncles,’ Feb. 
1870, p. G90. 
3 ‘ The American Beaver and his 'Works,’ 1868. 
4 4 The Principles of Psychology,’ 2nd edit. 1870, pp. 418-443 
