That's a generalisation and it's invalid like all generalisations.
That said, it's more likely that someone whose life ended in poverty is not as smart as someone who can live comfortably. IQ generally correlates with income (you can google a few studies).
There are surely tons of reasons that can push smart people into poverty (bad health, poor environment leading to poor choices) but that shouldn't obscure the general trend.
That said, I think over a certain IQ, other traits of your personality or the environment will have the predominant effect in determining whether you'll end up poor or not.
Similarly, over a certain amount of money, I'm sure there will be more variance. Making 5k more than your peers doesn't mean you're smarter than them - and the fact that you're all able to earn a living and save some money means you're all smart.
That said, it's more likely that someone whose life ended in poverty is not as smart as someone who can live comfortably. IQ generally correlates with income (you can google a few studies).
There are surely tons of reasons that can push smart people into poverty (bad health, poor environment leading to poor choices) but that shouldn't obscure the general trend.
That said, I think over a certain IQ, other traits of your personality or the environment will have the predominant effect in determining whether you'll end up poor or not.
Similarly, over a certain amount of money, I'm sure there will be more variance. Making 5k more than your peers doesn't mean you're smarter than them - and the fact that you're all able to earn a living and save some money means you're all smart.