During CNN’s seven-hour Democratic town hall on climate change, ambitious and outlandish claims weren’t exactly in short supply.

Sen. Kamala Harris indicated she wanted to ban fracking , while Sen. Elizabeth Warren promised to not “build any nuclear power plants” during her administration, even though nuclear power is one of the best ways to fight climate change. Yet it was a response from Sen. Bernie Sanders that offers the most cause for concern.

When Sanders was asked if he would be “courageous enough” to make some form of population control “a key feature of a plan to address climate catastrophe,” without hesitation, he said “the answer is yes.”

The specifics of what that may look like under a President Sanders aren’t entirely clear just yet, but Sanders, like many others, seem to believe that population is a key contribution to many of the problems we face. This is by no means a new line of thought, as the discussion around population control has actually had a resurgence in recent years. In fact, Sanders is echoing the ideology of one of the most popular villains in cinema: Thanos.

Like Sanders, the Mad Titan Thanos believed that the world (and in his case, the universe) was overflowing with life, and if this wasn’t soon balanced, all life would cease to exist. This thinking drove every action Thanos took in the Marvel Cinematic Universe. He found a possible solution through the “infinity stones” that could eliminate half of all life in a snap, and his quest for universal balance culminated in the films Avengers: Infinity War and Avengers: Endgame.

Thanos was the ultimate example of a central planner, and his storyline illustrates the inevitability of authoritarians with good intentions. Throughout Infinity War, he wasn’t acting evil for evil’s sake, he had a clear reason to believe what he believed, and his convictions drove everything he did. Then, after the Avengers showed Thanos how his plans would fail, instead of accepting that he was wrong, he doubles down and seeks to eliminate all life rather than half.

This escalation, illustrated through Thanos, is how many central planners start from ideas of peace, balance, and tranquility but end up with bloodshed and authoritarianism.

Now, Sanders is not Thanos, and he likely wouldn’t take steps as extreme as Thanos does to achieve population control. But much like Thanos, Sanders doesn’t understand that once his plans inevitably fail, he will be forced into a situation to either abandon his mission or double down into a much darker place.

Neither Sanders nor Thanos are the first to suggest population is running out of control. Paul Ehrlich popularized the idea back in the 1970s with the release of his book The Population Bomb. He claimed millions would starve to death due to overpopulation within a decade.

Before Paul Ehrlich, there was Thomas Malthus, who wrote a book in 1798 titled An Essay on the Principle of Population. He suggested that population would lead to humanity’s doom almost 200 years before Ehrlich.

Yet regardless of whether the claim came from Malthus, Ehrlich, Sanders, or Thanos, they all were wrong. Despite the incredible rise in population over the past 200 years, we have more abundance of food, not less. People have a higher standard of living , not a lower one. Basically, what’s happened is the opposite of everything they predicted.

This is because the world has been adopting a freer market to solve global problems. If we expect to solve the many problems we still face around the world, we must reject central planners such as Bernie Sanders and Thanos, and reject population control, too.

Caleb Franz is a libertarian writer, executive director of The MilLiberty Initiative, and the host of the MilLiberty podcast.