EXOD1075 Telling lies-- that is, knowingly and intentionally telling someone something that you know to be false--undermines people’s trust in one another. Indeed, at the extreme--that is, if everyone lied so often that one could never assume that the next person was telling the truth--social cooperation, commerce, and even friendships and family relations would become impossible. We would all be living in a fantasy world, and a terrifying one at that. It is not surprising, then, that the Torah specifically prohibits lying: “You must not carry false rumors (shaima shav, literally, “worthless words to be heard”) … Keep far from falsehood (sheker)” (Exodus 23:1, 7) and “You shall not steal; you shall not deal deceitfully nor lie to one another ” (Leviticus 19:11). The Rabbis understood the social consequences of lying: “This is the penalty for the liar: even when he tells the truth, no one believes him” (Babylonian Talmud, Sanhedrin 89b). They also condemned it as a form of theft, indeed the worst form of theft: “Stealing a person's thought [genevat da’at, i.e., deception] is the worst form of theft” (Tosefta, Bava Kamma 7:8). Why did the Rabbis think of lying as the worst form of theft? Why is it worse than stealing money or property from a person? One answer is that even though people who have been robbed often feel personally violated, in the end it is one’s property that the thief has encroached upon, not one’s person. Often the thief does not even know the person from whom he or she has stolen. Deception, though, is immediately and directly personal: the liar did not think enough of you to tell the truth, and so you rightly feel dishonored and molested. We will see below how the Rabbis make the same distinction between one's property and person with regard to slander.