Analogies between biological and social processes can be interesting; analogical thinking can suggest cause-and-effect relationships but does not prove their existence. When social evils follow an ingravescent course, they can be characterized as malignant. Both forms, biological and social, are parasitic, self-perpetuating, and invasive. Both malignancies arise from the normal and in some cases can be normalized again, but frequently there is an irreversible tendency to escape control. There are varieties of each, patterns of causes are complex, some having an important genetic component, and all influenced importantly by nongenetic factors. Each tends to recur following suppression by treatment, and in many instances the response is like that of a wounded hydra. Both social and biological malignancies tend to drain the substance and energy of the host and, kamikaze-like, threaten its life. There is a parellel between views of an earlier day that cancer is caused by the sins of