In Moral Essays, Seneca expresses his Stoic philosophy on providence, steadfastness, anger, forgiveness, consolation, the happy life, leisure, tranquility, the brevity of life, and gift-giving.

Volume II contains On the Good Life (outlining the Stoic program of living according to nature), On Leisure, On Tranquility (in which Seneca suggests a way of life that will bring contentment), On the Brevity of Life (which argues that intellectual pursuits and a proper understanding of time will make full even a short life), and the three Consolations (to Marcia, to Helvia, to Polybius).