I'm sure Socrates and Plato asked themselves the same question: if you cheat on the football pitch in order to aid your nation's World Cup campaign, does it count as cheating, and is it still "wrong"?
Luis Suárez , who handled the ball on the goal line and was sent off, but in doing so saved his country from ignominious defeat in the World Cup at the hands of Ghana in last night's quarter-final, in the injury time portion of extra time, is a hero tonight on the streets of Montevideo.
But should he be? Isn't cheating always wrong? What do you think? I'm torn. I'd have done the same thing as Suárez. But does that make it "right"?
Last week, the US philosopher and ethicist Peter Singer wrote a piece on the Guardian's Comment is Free  site, arguing that it's as wrong to cheat in football as it is in any other walk in life, focusing on the German goalkeeper Manuel Neuer's decision to grab the ball -- after Frank Lampard had scored! It had crossed the line! -- and put it back into play.
Here's how Singer put it:
To put it bluntly: Neuer cheated, and then boasted about it.
By any normal ethical standards, what Neuer did was wrong. But does the fact that Neuer was playing football mean that the only ethical rule is "win at all costs"?
In football, that does seem to be the prevailing ethic. The most famous of these incidents was Diego Maradona's goal in Argentina's 1986 World Cup match against England, which he later described as having been scored "a little with the head of Maradona and a little with the hand of God". Replays left no doubt that it was the hand of Maradona that scored the goal. Twenty years later, in a BBC interview, he admitted that he had intentionally acted as if it were a goal, in order to deceive the referee.
Something similar happened last November, in a game between France and Ireland that decided which of the two nations went to the World Cup. The French striker Thierry Henry used his hand to control the ball and pass to a team-mate, who scored the decisive goal. Asked about the incident after the match, Henry said: "I will be honest, it was a handball. But I'm not the ref. I played it, the ref allowed it. That's a question you should ask him."
But is it? Why should the fact that you can get away with cheating mean that you are not culpable? Players should not be exempt from ethical criticism for what they do on the field, any more than they are exempt from ethical criticism for cheating off the field, for example by taking performance-enhancing drugs.
Do you agree with him?