'Wap. III. 
MORAL SENSE. 
83 
tile indirect result of any otlier faculty ; it must there- 
fore have been directly acquired. On the other lianc , 
tile habit followed by the males of some social animals, 
of defending the community and of attacking their 
demies or their prey in concert, may perhaps have 
originated from mutual sympathy ; but courage, and 
in most cases strength, must have been previously 
Acquired, probably through natural selection. 
Of the various instincts and habits, some are muc 
stronger than others, that is, some either give more 
Pleasure in their performance and more distress m their 
Prevention than others ; or, which is probably quite as 
Important, they are more persistently followed throng 1 
inheritance without exciting any special feeling of plea- 
sure or pain. We are ourselves conscious that some 
habits are much more difficult to cure or change than 
°thers. Hence a struggle may often be observed in 
animals between different instincts, or between an 
instinct and some habitual disposition ; as when a dog 
bushes after a hare, is rebuked, pauses, hesitates, pursues 
again or returns ashamed to his master ; or as between 
ihe love of a female dog for ber young puppies and for 
her master, for slie may be seen to slink away to them, 
as if half ashamed of not accompanying her master. 
But the most curious instance known to me of one 
instinct conquering another, is the migratory instinct 
conquering the maternal instinct. The former is won- 
derfully strong; a confined bird will at tlie proper 
season beat her breast against the wires of her cage, until 
if is hare and bloody. It causes young salmon to leap 
() ut of the freshwater, where they could still continue to 
tive, and thus unintentionally to commit suicide. Every 
one knows how strong the maternal instinct is, leading 
even timid birds to face great danger, though with 
hesitation and in opposition to the instinct of self- 
