> ...Today, we are rulers of the world, but in the end the rocks and the seas will remain, and we will vanish without trace, leaving the planet as if we had never been.
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> That is a pretty sobering thought. It’s like sticking your hand in a bucket of water. You can see your hand in that bucket of water as others can see, but when you pull your hand out there is no trace of your hand ever having been there.
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A hand in water can create waves. If those waves are confined inside a bucket, when the hand is removed the water soon becomes still so no one can see that a hand was there. If that same hand is plunged into a river and creates waves, those waves can travel to affect other life in the river after the hand is pulled out.
-Mary C.