Huh. Most of the smartest people I know are really pretty lazy. They'll put a lot of effort into something they care about, but they're usually aware of the effort-to-reward ratio.
The hardest workers I know are the ones of ordinary intelligence. They have jobs that require more hours for less money, and often have families to take care of as well.
I don't think of anybody in my circle of acquaintances who's genuinely dumb, so I can't vouch for what happens once intelligence really dips far below average. Still, my anecdotal experience is that the really smart people are only kind of ordinarily diligent.
The hardest workers I know are the ones of ordinary intelligence. They have jobs that require more hours for less money, and often have families to take care of as well.
I don't think of anybody in my circle of acquaintances who's genuinely dumb, so I can't vouch for what happens once intelligence really dips far below average. Still, my anecdotal experience is that the really smart people are only kind of ordinarily diligent.