The fisher and the little fish

It happened that a fisher, after fishing all day, caught only a little fish.
“Pray, let me go, master,” said the fish. “I am much too small for your eating just now. If you put me back into the river I shall soon grow, then you can make a fine meal off me.”
“Nay, nay, my little fish,” said the fisher, “I have you now. I may not catch you hereafter.”
Moral: A little thing in hand is worth more than a great thing in prospect