The process by which young
children are taught how to be
continent. It's a rather strange process since it involves learning to exercise conscious control over one's bodily processes--and once we learn this control, it's almost impossible to
unlearn it.
I'm surprised that people who talk about biofeedback, meditation, and other forms of mind over matter don't point out that all of us have learned to exercise a profound level of control over bodily functions that aren't "naturally" conscious.
Of course, the unnatural quality of potty-training has been pointed out by some, notably Freud who coined the famous term anal-retentive and the less famous, but even funnier, anal-expulsive to describe psychological problems which he thought derived from problems in potty-training. Luckily for parents, his theories have later been shown to be false.