Ah, behavioural economics. Remember when we imported evolutionary biology into psychology and how suddenly neither field had any stupid ideas in it? It looks like we’ve done it again. Astonishingly, hungry people value filling, energy-dense food a lot. Well, yes. That’s what the word “hungry” means.
You should never make decisions about food when you are starving. When you go to the supermarket hungry, the food you are drawn to is high-calorie junk food,” said Dr Alain Dagher, a neurologist at the Montreal Neurological Institute. “You assign way too much value to calories and so way too little to health and other things.”
No, you should never make decisions about food when you are starving. By the same logic, I suppose, you should never make decisions about money when you are poor, or about charity when you are rich. Of course, if you’re hungry it is rational to want calories. You do, in fact, want calories in the old sense of the word “want” – you need more of them. Presumably, you should wait until you aren’t as hungry before deciding what to eat?
Before we descend into cheap snark, there’s an important point here. Dagher is quoted down at the bottom of the article as saying that this may explain why people who miss meals and eat at irregular hours tend to get fat. Fair enough, and good advice. But the problem is that by the time you get off the third bus and stand in front of the aerosol-cheese aisle, you’re hungry. You’re not somehow faking it, and signs lecturing you about healthy eating aren’t going to stop you eating. The point is to avoid getting into this position in the first place, which might involve things like changing jobs or moving that are difficult and require resources.
Similarly, fans of “nudge” tend to complain that poor people make bad decisions about money, typically by prizing cash up front above everything. To put it in econospeak, irrational discounting leads them to have extremely high liquidity preference. But liquidity is useful, and people tend to want it if they are facing a dangerously uncertain future. And typical reasons to need cash fast include things like “topping up the electricity meter”, “the kids are hungry”, “collection goons are threatening physical violence”. It’s not as if they don’t need cash on hand for very good reasons.
Where is the line between responses that are merely insufficient, and ones that actually tip over into mockery?