Definition
Virtue as habit is the recognition that character is not a single decision but the accumulated weight of many. The Stoics, inheriting an idea also central to Aristotle, taught that we become just by doing just acts and temperate by doing temperate ones. Virtue is the trained result of repeated practice.
On this view a virtue is a hexis, a stable condition of the soul. It is reliable precisely because it has been built up over time, so that the right response no longer depends on mood or effort.
Why it matters
How it works
Each time a person acts well, the corresponding disposition is reinforced; each time they yield to impulse, the opposite is strengthened. Virtue grows the way a path is worn into ground, through repetition. The Stoics therefore emphasized daily exercises and small, deliberate acts of restraint and courage.
The aim is to make virtuous action automatic rather than effortful. A mature practitioner does not deliberate at length about whether to keep a promise; the habit has become second nature, and reason confirms what character already inclines toward.