I particularly agree with your first point. The idea that discipline is separate from motivation is not biologically plausible. Rather, discipline is a form of

I particularly agree with your first point. The idea that discipline is separate from motivation is not biologically plausible. Rather, discipline is a form of motivation. No one does anything that they don't receive gratification for doing. That one can imagine circumstances where they would receive even more gratification (ie, 'if that gun weren't being held to my head, I would prefer sitting on the couch to carrying this rock') is irrelevant. People with discipline receive gratification in their brains when they exercise that discipline. It's a learned response and you can train yourself or others to exhibit it with either a carrot or a stick, until the gratification is internalized.