A traveller was walking along a beach when he saw a woman scooping up starfish off the sand and tossing them into the waves. Curious, he asked her what she was doing. The woman replied "When the tide goes out it leaves these starfish stranded on the beach. They will dry up and die before the tide comes back in, so I am throwing them back into the sea where they can live."

The traveller then asked her "But this beach is miles long and there are hundreds of stranded starfish, many will die before you reach them - do you really think throwing back a few starfish is really going to make a difference?" The woman picked up a starfish and looked at it, then she threw it into the waves.

"It makes a difference to this one" she said.