Imagine two rooms, each with a caged bear. The bear is not happy being in a cage. A rich man, and a poor man, are ushered into their respective rooms, and told that the lock on the cage isn't all that reliable.
I'd wager that they'd both suffer roughly equally on a provided IQ test.
If you can't afford it, that car repair is an existential threat.
You don't get that car fixed, you don't get to work, you lose your job, and then everything else that goes with that. Not to mention figuring out what you're going to do while your car is in the shop. Maybe you skimp on the repair, just do what you need to get it running again, and hope it doesn't turn into a bigger problem down the road.
If you can afford it, it's an inconvenience.
You drop your car off with the mechanic, get a rental or just Uber it to work, and pick up your car when it's ready. You'll pay to fix things properly, of course, because you can.
I think it's not scarcity itself, but constantly living under existential fear that causes so many problems.
Correct: it's not money per-se, it's about desperately needing money in a society where money are crucial for survival.
Often economists make the mistake of equating poverty == no money.
Instead, not all economies are money-driven.
Modern humans have existed for something like 100,000 years give or take a few tens of thousands, and yet we only started building anything particularly innovative in the last ~10,000 or so. So we spent 90% of our species' history doing very little in the way of cognitively challenging innovation.
I wonder if this might not be the reason. Some have observed that hunter-gatherers often had better nutrition and were healthier than at least early civilized humans, but maybe they also lived under a perpetual cloud of fear about the next famine, raid, or plague. Maybe that basically shut down their capacity for higher cognition. Maybe they didn't have any time to sit down and think and do so free of concern about the future.
In my limited experience with these people, they are absolutely capable of higher cognition, including planning into the distant future.
So, what to do if you are conservative politician and want more voters? Do you try to make poor people better or worse off given these two data points (whose scientific validity I am not able to judge, but I have to admit, they do seem to make sense)?
[1] https://www.sciencedirect.com/science/article/abs/pii/S01602...
"Scarcity: Why having too little means so much" is a great book on this.
In essence it is not that people in poverty have less innate executive control / cognitive capacity, but that the situation of poverty causes anyone to lose some significant points of executive control / cognitive capacity.
There are some illuminating (but terryfing) experiments in the book, where they show you can literally sabotage a low income persons score on an IQ test by mentioning a hypothetical car repair of 2000 dollars before they take it.