More on this from the Center for Teaching at Vanderbilt University.
“…the faculty of voluntarily bringing back a wandering attention,
over and over again, is the very root of judgment, character and will.
No one is compos sui if he has it not. An education which should
improve this faculty would be the education par excellence.”
[William James, 1890]
compos sui = master of one’s self
Dr. V 