Discrimination is what makes insurance work. An insurance regime where everyone pays the same amount is called "community rating." That sounds fair. No more cruel discrimination against the obese or people with cancer. But community rating is as destructive as ordering flood insurance companies to charge nothing extra to insure a very vulnerable beach house, writes John Stossel, or ordering car insurance companies to charge Lindsay Lohan no more than they charge you. Such one-size-fits-all rules take away insurance companies' best tool: risk-based pricing. Risk-based pricing encourages us to take better care of ourselves.