I have a pill that will make you a psychopath. You will retain all your intellectual abilities and all understanding of moral theory, but your emotional reactions to others suffering will cease. You will still have the empathy to understand that others are suffering, but you won't feel automatic sympathy for it.

Do you want to take it?

If the pill also removes the ability to feel shame I'll take it.

I wouldn't necessarily recommend it to most people and wouldn't want myself to have taken it while young. But at 30 my ethical principles are rather firmly entrenched in abstract concepts and powered by ego and stubbornness, rather than the sympathy that originally caused the ideals to be formed. These days the emotions just get in the way---they are far too sensitive to be useful to me and tend to be a significant liability.