It began as a classic David v Goliath¹ struggle. A fortnight ago Magnus Carlsen - the reigning world chess champion - lost a match against a 19-year-old American called Hans Niemann.

It was big news. But what happened next tore the chess community apart. Carlsen pulled out of the tournament. He then tweeted a video of football manager Jose Mourinho saying: "If I speak, I am in big trouble."  

Rumours that Carlsen was implying that Niemann had cheated stormed through the chess world. Some claimed that Carlsen's opening moves were leaked to Niemann. Others even suggested that the American inserted a remote control device into his buttocks that would vibrate to tell him what to do.

For Carlsen, a loss to Niemann is humiliating. The Norwegian is the highest rated chess player in history. He has a record streak of 125 unbeaten matches. He is to chess what Roger Federer was to tennis, except without a Rafael Nadal-level rival.

Niemann denied all allegations. He has even offered to play naked. But the sagaA long and epic story. is far from over. This Monday, Carlsen left an online game against Niemann after a single move. Interviewed yesterday, the champion again implied that he was unable to comment.

This is not the first time Niemann has been accused of cheating. He was banned from the website Chess.com after using a computer programme to trick the system.

He claims he has since stopped. Leading chess analyst Dr. Kenneth Regan examined his last two years of games and concluded that there is no reason to suspect foul play.

Cheating has a long history in chess. In 1978, grandmasterA title awarded to the world's very best chess players. Viktor Korchnoi accused Anatoly Karpov of cheating by receiving flavour-coded yoghurt from his team.

In 1985, a male British champion was suspended after disguising himself to compete in a women's chess championship. More recently, numerous players have been caught using computers and tablets during bathroom breaks.

Cheating is punished harshly in competitive chess. And it is difficult to deny that it disrupts the game. It makes it hard to assess who is the best. It rewards those who break the rules, sometimes with hefty prize packages.

In wider society, cheating disrupts fairness, the idea that we should treat people equally. As former US first lady Michelle Obama says: "success doesn't count unless you earn it fair and square."

Yet others think that cheating can be used for good. To cheat is to break the rules. If the rules are themselves unfair - such as in an oppressiveInflicting harsh and unfair treatment. society - cheating can be an act of resistanceThe refusal to comply or go along with something. . 

Cheating in war is often praised. The Greek hero Odysseus is celebrated for tricking the Trojans with his Horse.² The AlliedRelating to Britain and its allies in World War One and Two. effort in World War TwoA global war that lasted from 1939 to 1945 and included all of the great powers. was hugely aided by secret agents who operated aside from the "rules" of war. As novelist Daniel DefoeAn English trader, writer, journalist, and spy. His novel Robinson Crusoe is considered one of the first English novels. wrote: "'Tis no sinSomething that is immoral, often in religious law. to cheat the devil."

To cheat can be to be creative. Video game expert Tom Faber writes. "One of the most beautiful things about gaming... is that players are free to explore however they choose, even if it means rearranging those rules." Cheating can teach us to experiment and be creative.

Yes: In situations such as war, cheating might sometimes lead to the greater good. But the act itself remains wrong regardless. Before cheating, you should always weigh up the consequences.

No: It all depends on the context. To cheat someone out of a deserved prize might be bad. But breaking the rules can sometimes lead to better outcomes. Plus, cheating well is a talent in itself.

Or... Cheating relies on the idea of fixed rules that should not be violated. This may be the case in a board game. But life itself is fluid and complex. One side's cheating is another's stroke of genius.