One: “The system is interdependent and what I do is damaging it, but it doesn’t matter because I will die before it breaks in a way that hurts me.” This is rational. Rational thinking will not get you out of issues like climate change. Rational thought is a means, not an end.
Two: The system is interdependent and what I do is damaging it, but by doing so I am becoming more powerful, rich, or otherwise benefiting. If I was not damaging it I would not benefit as much, and might even suffer.
A lot of people worship rationality in our society. We think that rational is a synonym for “good” and that if we are rational, we will do the right thing.
This is incorrect for a variety of reasons, but it is extremely incorrect in group action problems. If 90% of society, and 95% of people born 50 years in the future will suffer because I do something, but I benefit greatly, it is entirely rational to cause that harm.
Covid has made the rich much richer, fast. Statista has a nice little graphic:

As for Climate Change, business as usual worked fine for the world’s elites. We really started paying attention to global warming in the 70s, and since then, by not just ignoring it but increasing it, they’ve done brilliant.

(The top .1% and .01% and .001% numbers have risen even faster.)
Rationality does not work for ethical decisions. It can help you determine means, “what’s the best way to do this” but it can’t determine ends.
It isn’t even that great for means. The rationalists (epitomized by Stars Slate Codex) tend towards hard utilitarianism: the most good for the most people, and sneer at virtue ethics.
Seems smart: what you want is the most good, right?
But the problem is that instrumenalism “the right thing is whatever gets you where you want to go” often doesn’t work because humans are both stupid and very good at motivated reasoning. “Well, people will obviously be better off if we tax rich people less, because rich people give jobs and they can give more jobs and pay more for them!”
Or, “if we pay people like CEOs more if they raise shareholder value, they’ll do more of the right thing!”
Or, in general terms, “people help others because of greed, not virtue, so we have to bribe them to do the right thing and micro-manage incentives.”
None of this stuff worked, of course. It never has, and it never will. The eras where you tax the rich heavily and keep executive compensation relatively low had better behaviour by executives than the post Thatcher/Reagan era. Faster economic growth, too. (Better isn’t necessarily the same thing as good.)
The problem with instrumentalist thinking, which utilitarianism tends to fall into, is that “means are ends.” If you bomb the village to save it, or invade the country, you’ve done a shit load of evil. If you lock people up in prison for victimless crimes, you’ve created victims: the people being brutalized in prison. If you let cops take people’s property without proving a crime, you’ve increased theft. If you torture, you’ve tortured. If you lower wages to increase efficiency, you’ve lowered wages. If you surveil workers to get the most out of them you know that’s bad (Bezos would never let someone else determine when he can take a shit.)
The means are always most of what we do.
We know that being greedy, or selfish, or cowardly, or sadistic are bad. We know that rape is always bad. We know that killing people is bad. We know that beating people is bad.We know that hunger is bad. We know that homelessness is terrible. We know lack of water kills. When the IMF removes food subsidies we KNOW more people will go hungry. When we sell bombs to Israel and Saudi Arabia, we know they’ll be used to murder innocents.
Instrumentalism and utilitarianism allow you to say to yourself “well, I know virtue ethics would say this is bad, but actually it’s good because it’ll lead to a better world.” Meanwhile there you are with policies that lead to the Amazon being clearcut and dumping so much CO2 and methane into the world that eventually the world’s forests just start burning down and permafrost methane starts exploding like bombs.
Virtue ethics and bars on behaviour like “no torture or rape ever” exist because we know we tend to find excuses to allow us to engage the worst parts of ourselves: to be greedy and selfish, to force others to do what we want, and to live like Kings and Queens because we exploited others. Bezos goes to space, workers in his warehouses piss into jars or wear diapers and walk around in shit before they pass out or die from heat stroke: these things are related.
Rationalism just says “how do I get what I want?” Virtue ethics and red lines say “you can’t get it by doing evil.”
This is why straight utilitarians and instrumentalists are either hypocrites or fools. Either they know that their ethics allows for monstrous behaviour and doesn’t guarantee results, or they know it produces subpar results for a lot of people, even most people, but they expect to be in the minority who benefits (which, by the way, is very rational.)
Don’t worship at the cult of rationalism or instrumentalism. Virtue ethics and red lines have their own problems, and there are reasons for being way of them too, but at the end of the day, if getting what you want requires you to hurt a lot of people, perhaps you aren’t doing it because you truly believe it’ll make the world a better place?
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