There's this:
"You can free things from alien or accidental laws, but not from the laws of their own nature. You may, if you like, free a tiger from his bars; but do not free him from his stripes".
Or this:
That you and a tiger are one may be a reason for being tender to a tiger. Or it may be a reason for being cruel as the tiger. It is one way to train the tiger to imitate you, it is a shorter way to imitate the tiger. But in neither case does evolution tell you how to treat a tiger reasonably, that is, to admire his stripes while avoiding his claws.
Either of these fit the bill Sandy?