Habits

A habit is a stable quality, a quality not readily changed, which disposes its possessor with respect to well-being or ill-being in himself or in his relation to things other than himself. For example, health is a habit; so is knowledge.

Habit is a distinct kind or species of quality.

Inasmuch as habit directly affects its possessor in well-being or ill-being, it extends to his operations. A habit which affects its possessor in himself (such as health, or fatness) is called an entitative habit; a habit which affects its possessor in his operation (such as the acquired skill of playing a musical instrument) is called an operative habit.

Now, whatever has reference to an operation has reference also to the end towards which that operation tends. Hence good habits are useful, and even necessary, to man for the attaining of the ends of his normal operations.