TheParadox of the Court, also known as thecounterdilemma of Euathlus orProtagoras' paradox, is aparadox originating inancient Greece.
The story is related by the Latin authorAulus Gellius inAttic Nights,[1] who says that the famoussophistProtagoras took on a promising pupil, Euathlus, on the understanding that the student pay Protagoras for his instruction after he wins his first court case. After instruction, Euathlus decided to not enter theprofession of law, but to enterpolitics instead, and so Protagoras decided to sue Euathlus for the amount he is owed.[2] Protagoras argued that if he won the case, he would be paid his money. If Euathlus won the case, Protagoras would still be paid according to the original contract, because Euathlus would have won his first case. Euathlus, however, claimed that if he won, then by the court's decision he would not have to pay Protagoras. If, on the other hand, Protagoras won, then Euathlus would still not have won a case and would therefore not be obliged to pay. The question is then, which of the two men is in the right?
Gellius concludes:
