> Isn't there a theory that any nootropic substance needs to have a downside or we would have naturally evolved it by now? Couldn't that be applied to all mode

> Isn't there a theory that any nootropic substance needs to have a downside or we would have naturally evolved it by now? Couldn't that be applied to all modern technology? Humans obviously weren't meant to fly or we would have evolved flight; therefore airplanes bad. Why is this any different? Evolution is an extremely blunt force with only so many tools at its disposal. Besides, there would need to be selective pressure for being happy and content with life, even into late adulthood. Is there? That's not clear at all.