Do you have a plan for the apocalypse? Have you sat down and developed a strategy to ride out a doomsday event? Sam Bankman-Fried, the founder of the bankrupt cryptocurrency exchange FTX, and his younger brother, Gabriel, certainly seem to have done so. According to details of a new lawsuit filed against FTX, the tech bros weren’t content with a run-of-the-mill billionaire’s luxury underground bunker. Nope, they had big plans to purchase the tiny Pacific island nation of Nauru as insurance against the world ending.

How would that work? Alas, details are sparse. The court filings simply allege that Gabriel Bankman-Fried wrote a memo to an unnamed FTX official suggesting they buy the island “in order to construct a ‘bunker/shelter’ that would be used for ‘some event where 50-99.99% of people die [to] ensure that most EAs [effective altruists] survive’”.

There were also plans to develop “sensible regulation around human genetic enhancement, and build a lab there”. The memo added: “probably there are other things it’s useful to do with a sovereign country, too”.

Admittedly, I am not an expert in doomsday prep. Still, buying Nauru seems an unusual disaster-mitigation strategy. At its highest point the island is only 65 metres above sea level, making it vulnerable to rising tides and global heating. There are no streams or rivers, which makes procuring fresh water a challenge. Rampant phosphate mining a few decades back ravaged the soil, meaning much of the land is infertile and more than 90% of food consumed in Nauru is imported. And then there’s the small fact that it’s a sovereign nation – where more than 12,000 people live – that isn’t for sale.

But what do I know? While the Nauru project may sound like a harebrained neo-colonialist scheme hatched after way too many beers in the pub (or, since this is Silicon Valley, too much LSD in the mindfulness room), it’s important to remember that the idea was devised by effective altruists.

In his heyday, Sam Bankman-Fried was the most famous face of effective altruism: a movement started more than a decade ago by the now 36-year-old Oxford philosopher William MacAskill, which defines itself as “using evidence and reason to figure out how to benefit others as much as possible”. Before young MacAskill came along, you see, all previous altruism was ineffective. Nobody in the do-gooder space thought at all about evidence or reason; everything was just based on vibes.

In its early days, EA was largely about “earning to give”. The idea was that the best way certain people could do good was to pursue a high-paying career, even in a morally dubious sector, and then donate much of their salary to charity. (“Working for a hedge fund could be the most charitable thing you do,” MacAskill argued in the Washington Post in 2015.) Unsurprisingly, this made it very popular among people earning tons of money in morally dubious sectors. Behold: a moral philosophy that stated that no systemic change was needed and your highly lucrative job made you a wonderful person.

In recent years EA has gone from being a niche interest to one of Silicon Valley’s favourite, and most influential, philosophies. As the movement has grown richer, its focus has shifted: it’s now increasingly about “longtermism”. The most important thing you can do, in line with this ethos, is ensure the long-term survival of humanity. Which might mean prioritising preventing the 0.0001% possibility of an AI-sparked extinction-level event in 100 years’ time over tackling the millions of deaths from poverty, disease and hunger right now.

I want to stress again that EA is a very serious and intelligent movement promoted by very serious and intelligent people because, to the untrained eye, it can sometimes look like a cult of unhinged narcissists. That Nauru project, for example? That wasn’t the only weird idea the folk at FTX had dreamed up in the name of effective altruism. According to the court filings, the FTX Foundation, the non-profit arm of FTX, had authorised a $300,000 (£230,000) grant to an individual to “write a book about how to figure out what humans’ utility function is (are)”. The foundation also made a $400,000 grant “to an entity that posted animated videos on YouTube related to ‘rationalist and [effective altruism] material’, including videos on ‘grabby aliens’”.

So there you go. Some of the best minds of our generation (or so they’d have you believe) are busying themselves with strategies on grabby aliens and Pacific island bunkers. Is this effective? Is this altruism? I can’t tell you for sure what the future of effective altruism is, but the road to hell is paved with good intentions.

• Arwa Mahdawi is a Guardian columnist

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