Mishnà su Levitico 26:78

Seven kinds of punishment come to the world for seven categories of transgression:When some of them give tithes, and others do not give tithes, a famine from drought comes some go hungry, and others are satisfied. When they have all decided not to give tithes, a famine from tumult and drought comes; [When they have, in addition, decided] not to set apart the dough-offering, an all-consuming famine comes. Pestilence comes to the world for sins punishable by death according to the Torah, but which have not been referred to the court, and for neglect of the law regarding the fruits of the sabbatical year. The sword comes to the world for the delay of judgment, and for the perversion of judgment, and because of those who teach the Torah not in accordance with the accepted law.

Rabbi Joshua and Rabbi Nehunia ben Elinathan, a man of Kefar Habavli, testified concerning a limb [separated] from a corpse that it is impure; whereas Rabbi Eliezer says: they declared [this] only of a limb from a living [man]. They said to him: is not there an inference from the minor to the major (kal vehomer): If in the case of a living man [who is himself pure] a limb severed from him is impure, how much more in the case of a corpse [which is itself impure] should a limb severed from it be impure! He said to them: they have [nevertheless] declared it only of a limb from a living man. Another answer: The impurity of living men is greater than the impurity of corpses, because a living man causes that on which he lies and sits to become capable of making impure a man and clothing, and [he causes also] what is over him to transfer impurity to foods and liquids- which is defilement that a corpse does not cause.