Cardinal virtues

Cardinal virtues are four virtues of mind and character in both classical philosophy and Christian theology. They are Prudence, Justice, Fortitude, Temperance. They form a virtue theory of ethics. The term cardinal comes from the Latin cardo (hinge);[1] virtues are so called because they are regarded as the basic virtues required for a virtuous life.

An image personifying the four virtues (Ballet Comique de la Reine, 1582)

These principles derive initially from Plato in Republic Book IV, 426–435 (see also Protagoras 330b, which also includes piety (hosiotes)). They were also recognized by the Stoics. Cicero expanded on them, and Ambrose, Augustine of Hippo, and Thomas Aquinas[2] adapted them while expanding on the theological virtues.