This lecture[1] about barefoot running by a Podiatrist has a great quote in it in response to the some bare foot enthusiasts saying, "Humans were born to run." "Humans were born with one purpose, to reproduce then die." I agree, All other "purposes"(happiness, satisfaction, etc.) serve this mandate, reproduction.

[1] https://www.youtube.com/playlist?list=PLGtryE0TPZPESgSYbVjQz...