Philosophy of science is about as useful to scientists as ornithology is to birds.
It is much better to learn the elements of geology, of botany, or ornithology and astronomy by word of mouth from a companion than dully from a book.
Aesthetics is for the artist like ornithology is for the birds.
Aesthetics is to artists as ornithology is to birds.
The fidelity of a dog is a precious gift demanding no less binding moral responsibilities than the friendship of a human being.
Music criticism should be to musicians what ornithology is to the birds.
[Audubon's works are] the most splendid monuments which art has erected in honor of ornithology.
As for fowling, during the last years that I carried a gun my excuse was that I was studying ornithology, and sought only new or rare birds. But I confess that I am now inclined to think that there is a finer way of studying ornithology than this. It requires so much closer attention to the habits of the birds, that, if for that reason only, I have been willing to omit the gun.
or simply:
