Another fallacy comes creeping in whose errors you should be meticulous in trying to avoid. Don’t think our eyes, our bright and shining eyes, were made for us to look ahead with. Don’t suppose our thigh bones fitted our shin bones and our shins our ankles so that we might take steps. Don’t think that arms dangled from shoulders and branched out in hands with fingers at their ends, both right and left, for us to do whatever need required for our survival. All such argument, all such interpretation is perverse, fallacious, puts the cart before the horse.
No bodily thing was born for us to use. Nature had no such aim, but what was born creates the use. There could be no such thing as sight before the eyes were formed. No speech before the tongue was made, but tongues began long before speech were uttered. and the ears were fashioned long before a sound was heard. And all the organs I feel sure, were there before their use developed. They could not evolve for the sake of use be so designed. But battling hand to hand and slashing limbs, fouling the foe in blood, these antedate the flight of shining javelins. Nature taught men out to dodge a wound before they learned the fit of shield to arm. Rest certainly is older in the history of man than coverlets or mattresses, and thirst was quenched before the days of cups or goblets.
Need has created use as man contrives device for his comfort. but all these cunning inventions are far different from all those things much older, which supply their function from their form. The limbs, the sense, came first, their usage afterwards. Never think they could have been created for the sake of being used. ~ Lucretius