Interestingly the challenge was finding a power source with enough thrust-to-weight for power flight. Heavier-than-air flight can be decomposed into "power sour

Interestingly the challenge was finding a power source with enough thrust-to-weight for power flight. Heavier-than-air flight can be decomposed into "power source," "stability of design," and maybe "scale". So for instance, Da Vinci came up with pretty good designs for heavier-than-air unpowered flight. Our current decomposition of mammalian intelligence seems somewhat weak in comparison: we've divided the mammal brain into regions, yes, but we still haven't made an accurate simulation at the electrochemical level of a functioning mammalian brain. That's not to say nobody has or is trying, only that our simulations are more like approximations at present. They also don't have good simulations of astrocytes and glia.