Feeling something striking you does not always equate to physical pain. A person with rock hard abs getting punched in the stomach will still feel it, but chances are, they will not be in any sort of pain. On the other hand, plenty of people have tried their bodies and their minds to simply ignore harsh physical pain without having any sort of significant muscle mass.

The majority of 'pain' a person feels when, say, a limb gets cut off, is mostly due to the shock of seeing their limb missing. Shock is not pain; it is a state of mind. If you get rid of that, if you can block that out, the pain is not there. Yes, I am saying that with enough mental discipline, a person can resist the pain of getting an arm or a leg cut off.

Naturally, a person can also resist emotional pain. They have names for this: Sociopathy, psychopathy, you name it. That is not discipline, however, that is due to a chemical imbalance. They are entirely different from each other.