Regarding emotion (used synonymously with the word "passion" in this context), which, following John Damascene, Aquinas defines as "a movement of the sensitive appetite when we imagine good or evil," Thomism repudiates both the Epicurean view that happiness consists in pleasure (sensual experiences that invoke positive emotion), and the Stoic view that emotions are vices by nature. Aquinas takes a moderate view of emotion, quoting Augustine: "They are evil if our love is evil; good if our love is good." While most emotions are morally neutral, some are inherently virtuous (e.g. pity) and some are inherently vicious (e.g. envy).