The Fox and the Goat explained simply

A Fox fell into a well and was unable to get out again. By and by a thirsty Goat came by, and seeing the Fox in the well asked him if the water was good. "Good?" said the Fox, "it's the best water I ever tasted in all my life. Come down and try it yourself." The Goat thought of nothing but the prospect of quenching his thirst, and jumped in at once. When he had had enough to drink, he looked about, like the Fox, for some way of getting out, but could find none. Presently the Fox said, "I have an idea. You stand on your hind legs, and plant your forelegs firmly against the side of the well, and then I'll climb on to your back, and, from there, by stepping on your horns, I can get out. And when I'm out, I'll help you out too." The Goat did as he was requested, and the Fox climbed on to his back and so out of the well; and then he coolly walked away. The Goat called loudly after him and reminded him of his promise to help him out: but the Fox merely turned and said, "If you had as much sense in your head as you have hair in your beard you wouldn't have got into the well without making certain that you could get out again." Look before your leap.