This is Kevin Durant: AP

Here is what you need to know about Kevin Durant, who did the crazy thing everyone is talking about.

Who is Kevin Durant?

Kevin Durant is probably one of the best basketball players in world history. In 2014, he won the NBA’s MVP award, and he’s currently third all-time in scoring per game behind only Michael Jordan and Wilt Chamberlain. Not only is he one of the best players in the NBA, he’s also one of its most recognizable and marketable faces.

In 2007, he was drafted by the Seattle SuperSonics, which moved to Oklahoma City in 2008 and became the Thunder. Durant has been with the franchise for all nine years of his career. In those nine years the Thunder grew into one of the best teams in the NBA, but they were never able to win a championship.

What did he do?

This summer, Durant became an unrestricted free agent. That means he could choose to stay with the Thunder or go play for any other team in the NBA. On the morning of July 4, he announced that he would be leaving the Thunder to sign with the Golden State Warriors.

Why are people mad?

The Warriors, like Kevin Durant, are outrageously good. Two seasons ago they won the championship, and last season they broke the NBA record for most wins in a season with a record of 73-9. If they had not choked the title away to LeBron James and the Cleveland Cavaliers, they might have had a claim as the best basketball team ever.

A team as historically great as the Warriors has never added a player as historically great as Kevin Durant. It’s just not supposed to happen. Sports leagues are designed to funnel prodigiously talented players (like Durant) to bad teams (like the Thunder), and to keep those players on those teams indefinitely once both player and team prosper. (Michael Jordan, for instance, was on the Bulls for close to 15 years.) Durant’s story—incredibly good player becomes a superstar in a city as random as Oklahoma City—is how we’re conditioned to consume and celebrate sports.

Durant severing that fairy tale story to join the team that just had the most wins ever shatters that conditioning. It’s a direct repudiation of how America understands sports. LeBron did something similar in 2010, but Durant joining the Warriors is an unprecedented marriage of talent that threatens to shred the basic notion of sports: that each team should have an equal opportunity at victory. What’s the point of having a league if one team now has the odds so slanted in their favor? Will watching basketball next season even be fun if you already know who is going to win?

Durant’s choice has become one of those stories that rises out of the sports pages because it feels not just wrong, but evil. Sportswriters have had to look not only outside athletics but outside reality to find what feels like a fair comparison: Deadspin, The Ringer, and ESPN’s The Undefeated all have likened the Warriors with Durant to the Star Wars Death Star, which looms in George Lucas’ galaxy waiting to destroy planets with one easy zap of a laser.

But Durant’s decision is such a major topic of discussion because it transcends sports. It touches topics that define the nature of a society. It asks us how we understand morality, fairness, and, ultimately, basic economic freedom.