I once had drinks with a hedge fund guy whose firm had been big into the kind of mortgage-backed securities that brought on the financial crisis. His colleagues, he told me, had foreseen the implosion of the housing market, but that hadn't stopped them from trading in exactly the securities they knew were making it inevitable.

When I asked why on earth they would do such a thing, he introduced me to a term I had never heard before, although I've thought about many times since: the trader's call. A call option, he explained, is a type of financial contract that allows an investor to make deals that have limited potential for loss but unlimited potential for gain. By giving him a cheap way out of bad investments, it allows the investor to make far more speculative bets than he would otherwise.

For hedge fund traders, my new friend went on, every deal is a sort of call option. They're gambling with clients' money, making fixed management fees plus a percentage of profits. If a trader does well, he can make hundreds of millions of dollars in a year. If he screws up, the worst thing that happens is he gets fired and walks away with the pile of money he's made already. That's the trader's call. In this scenario, it's irrational for a trader to do anything except make ultra-risky bets--even on securities he knows will eventually tank at some point.

I thought about the trader's call when I read the news that Peter Thiel, the billionaire venture capitalist who supported Donald Trump's candidacy and advised him during the post-election transition, has secretly been a citizen of New Zealand since 2011 and owns a large rural estate there. A New Yorker story on ultra-wealthy "doomsday preppers" identified Thiel as one of a number of Silicon Valley and Wall Street billionaires who have purchased property in New Zealand in the belief that the island nation will remain a safe haven should catastrophes make large parts of the globe dangerous or uninhabitable.

You could argue that many super rich preppers have contributed to geopolitical instability in one way or another--by building internet platforms that give voice to hate groups and help disinformation go viral (Reddit co-founder Steve Huffman is prominently featured in the New Yorker story), or by supporting taxation policies that drive extreme wealth inequality. Thiel has promoted instability much more directly with his support of Trump, whose administration has made clear its desire to remake the existing world order. Thiel stated during the campaign that Trump offered a better hope of peace than Hillary Clinton, but Trump's closest adviser has said he expects to go to war with nuclear-armed China within a decade and envisions a civilizational clash with the entire Muslim world as well. And that's not even factoring in Trump's reported comments about the use of nuclear weapons, his skepticism about climate change, or his outspoken admiration for authoritarian foreign leaders.

Thiel has pointed out, reasonably enough, that America's political system is stuck in a long period of gridlock and the current generation of young Americans faces dimmer financial prospects than their parents did. To alter those trend lines requires leaders willing to depart from the status quo, he says. While it's hard to disagree with any of that on the face of it, even Thiel's utopia-minded peers in Silicon Valley think he is wrong if not crazy to think Trump can deliver the right kind of change.

To understand why he doesn't listen to them, it's helpful to know something else about Thiel: He is deeply invested, philosophically and financially, in the idea of extreme human life extension. Thiel has told me and other interviewers he believes it's possible, or even likely, that, during his lifetime, advances in medical science will extend the human lifespan at an ever-faster rate until it's increasing faster than the rate of aging. At least, he believes this will be true for people with access to longevity treatments--and Thiel's $2.7 billion fortune and deep ties to biotech companies make him a good bet to be one of the first to benefit.

Most of us, I'd wager, don't spend a lot of time thinking about immortality or the distant future. We accept that we'll die someday. The most we can really hope for is for the world to be a good place while we're here, and for it to be kind to our children and grandchildren and the other loved ones we leave behind.

The earnest belief that one could live forever or something like it changes this math. If you really think you'll exist 500 or 5,000 years, the happiness of Earth's inhabitants in the next 50 or 100 years becomes a lot less material. Sacrifices that seem extreme in the context of a single generation look more reasonable when you amortize them over a millennium or two. What's important is that the events that unfold now put humanity on the right long-term trajectory. Thiel has supported the work of philosopher Nick Bostrom, who argues for weighing the value of the trillions of lives that will exist in the future in today's ethical calculations. Thiel has hinted at a similar view, writing,

The future will be much better or much worse, but the question of the future remains very open indeed. We do not know exactly how close this race is, but I suspect that it may be very close, even down to the wire. Unlike the world of politics, in the world of technology the choices of individuals may still be paramount. The fate of our world may depend on the effort of a single person who builds or propagates the machinery of freedom that makes the world safe for capitalism.

Emphasis mine.

Think of it this way: If you live in a rental that's somewhat rundown and needs a noisy, messy renovation to be beautiful, you won't encourage your landlord to undertake that work. Why make things unpleasant for yourself and the neighbors? Better to just do what you can to make it livable until you move.

If, however, you own the house and plan to stay in it for a long time, you'll be eager to get started with the renovation right away. The sooner you do, the sooner you'll be living in your dream home. The idea that you should defer to the sensibility of neighbors who might move away in a few months seems overly nice. Of course, if the work gets really messy, you might need somewhere else to crash for a while. That's where New Zealand comes in.

Which brings us back to the trader's call. For most of us, life is a bet with limited upside and all-too-tangible risks. No matter how much wealth you might amass, you will eventually die and leave it behind. If you're very lucky, you'll do so with the satisfaction that those you leave behind will be financially taken care of--but you won't be around to safeguard them from whatever else might befall them.

For Peter Thiel, these aren't the stakes at all. Thiel--who, let us not forget, is not just a venture capitalist but a hedge fund founder--has controlled his downside exposure in a volatile world with his New Zealand estate and citizenship, and whatever other emergency readiness plans he might have. His upside, meanwhile, is limitless: a potential eternity of health and wealth. Like the Wall Streeters who knowingly brought on the financial crisis, he can gamble with the fates of billions, secure in the knowledge he's behaving with perfect rationality.