Knees: Passive value
Tad McGeer proved that you don’t need knees to walk downhill. But he also proved that downhill walking is nicer with knees.
He further proved that you don’t need a brain if all you want to do is walk down a slope. Nor do you need much else. Just a pair of legs - call them stand-alone legs, if you like - will do it.
McGeer proved these things mathematically. Then he proved them in a way that non-mathematicians seem to find more persuasive….
So begins this week’s Improbable Research column in The Guardian.