http://www.livescience.com/6115-humans-walk-flat-footed.html

I love how they do this.. its absolutely fascinating. They make the claim that walking flatfooted is more energy efficient(and thus why we 'evolved' that way) yet completely ignore the fact that if we weren't walking flatfooted to begin with it would not only have been less efficient, but it would have been impossible as the angle of the joints and the length of the tendons would not have allows us to put our heels down.

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What is the purpose of living? How about, 'to reduce needless suffering. It seems to me to be a worthy purpose.