Suppose that you knew your body could produce its own morphine. Would you still take as much aspirin — which can make your stomach bleed — for mild headaches?
If you knew having a support network and being optimistic had the same biological effect on depression as a pill, would you be less likely to try Prozac — which can have side-effects from sexual dysfunction to suicidal tendencies?
What about the fact that placebo knee surgery is as good as the real thing — would you choose the surgeon’s knife before physiotherapy?