Three blonde men are stranded on one side of a wide river, and don't know how to get across.
The first man prays to God to make him smart enough to figure out how to cross the river. So God turns him into a brown-haired man and he swims across.
The second man prays to God to make him even smarter. So God turns him into a dark-haired man and he builds a boat and rows across.
Then the third man prays to God to make him the smartest of all. So God turns him into a woman and she walks across the bridge.