But let me give you an example of a profoundly carcinogenic environment. It's called a prison. You take loneliness, you take depression, you take confinement, and you add to that, rolled up in a little white sheet of paper, one of the most potent neurostimulants that we know, called nicotine, and you add to that one of the most potent addictive substances that you know, and you have a pro-carcinogenic environment. But you can have anti-carcinogenic environments too. There are attempts to create milieus, change the hormonal milieu for breast cancer, for instance.