A man was walking along the ocean, and observed another person on the beach as well. As he watched, every couple of feet the man repeatedly bent down, and threw something into the ocean.
Puzzled, the man asked, "What are you doing?"
He simply replied, "Throwing the star fish back into the ocean." And picked yet another one up, and tossed it into the waves.
"Why?" asked the man, still puzzled.
"Because the tide is low, and they will dry out and die otherwise."
The man watched him throw a few more starfish and became exasperated. "This beach goes on for miles! And there are hundreds of star fish per mile! You can't possibly save enough to make a difference!"
In response, he picked up another star fish and tossed it into the ocean. "It made a difference to that one."