How do you know whether a Kurd is lying?

"How do you know whether a kurd is truthful or lying?" The question is regarded by some philosophers as the second most perplexing one. Hay served as an administrator and commander in the British Army. He was in Kurdistan from 1918 to 1920 for two years. He had to write about the philosophical riddle, as was to be expected:

A common form of settlement for a dispute is by oath. If A has accused B of stealing his donkey, and cannot adduce sufficient proof to secure a conviction, he can call upon B to swear that he has not taken the animal. If B refuses to swear, he is the guilty party; if he takes the prescribed oath, the case is dropped. An arbitrator in a case may call upon either of the parties to take a similar oath.

There are several forms for an oath. The commonest practice is to swear by the Name of God, "Wallahi, Billahi, Tillahi." To make it more impressive this oath may be sworn on the Quran. The Kurd, however, is a trained liar, and will perjure himself several times in a day. One of them once said to me, "As soon as a Kurd starts swearing, disbelieve him." If a man says, "By God and His Prophet, by the Holy Quran, by all my ancestors and the head of my father, I was not in the village the day the donkey was stolen," one may be pretty sure he was there the whole time. If, however, he plucks the left side of his coat with his right hand and shakes it saying, " I have heard, but I am not sure, I wouldn't swear an oath to it, that Qadir sold his land to Rashid Agha ten days ago for fifty pounds," there is little doubt that he is speaking the truth.