“One report that particularly impressed me appeared in the prestigious journal Science in April 1982 by authors Visintainer, Volpicelli, and Seligman. They described a group of rats, all suffering from the same cancer, that were exposed to annoying electric shock under two different experimental conditions; one group could escape from it, and the other had to take it until it stopped. Both groups got exactly the same dose of shock; the ability to escape from it was the only difference between the two groups. According to the authors, "Rats receiving inescapable shock were only half as likely to reject the tumor and twice as likely to die as rats receiving escapable shock or no shock. Only 27 percent of the rats given inescapable shock rejected the tumor, compared to 63 percent of the rats given escapable shock and 54 percent of the rats given no shock."

The clear implication of the study was that the immune systems of the rats that were more emotionally stressed were less efficient, since it is the effectiveness of the immune system that determines whether a cancer will be thrown off or not. If this is the case with rats, imagine how much more important the emotions must be in humans. (page 185)”