Tommy Caldwell

Stand at the base and look up at 3,000 feet of blankness. It just looks like there's no way you can climb it. That's what you seek as a climber. You want to find something that looks absurd and figure out how to do it.

By irreducibly complex I mean a single system composed of several well-matched, interacting parts that contribute to the basic function, wherein the removal of any one of the parts causes the system to effectively cease functioning.