The typical human emotions include love, grief, fear, anger, joy. Each indicates a state of some kind of arousal, a state that can prompt some activities and interfere with others. These states are associated with characteristic feelings, and they have characteristic bodily expressions. Unlike moods they have objects: one grieves over some particular thing, or is angry at something. Different philosophical theories have tended to highlight one or other of these aspects of emotion. Pure arousal theory imagines a visceral reaction triggered by some event, which stands ready to be converted into one emotion or another by contextual factors. Theories based on the feel or qualia of an emotion were put forward by writers such as Hume and Kant, but the approach meets difficulty when we consider that an emotion is not a raw feel, but is identified by its motivational powers, and their function in prompting action. The characteristic expression of emotion was studied extensively by Darwin, resulting in the classic The Expression of the Emotions in Man and Animals (1872). In 1884 James published what became known as the James-Lange theory of emotion whose main contention is that we feel as we do in virtue of the bodily expressions and behaviour that we are prompted towards, rather than the other way round: ‘our feeling of the changes as they occur is the emotion’. Again it is not clear how such a theory would accommodate the directed, cognitive side of emotions that have a specific object, rather than being simply the experience of bodily change. Directly opposing this some philosophers have put forward a purely cognitive theory of the emotions, derived from Stoicism, seeing them simply as judgments: fear of the dog is no more than the judgement that it is dangerous or a threat to one’s well-being. The Stoics thought that as judgements the emotions were typically false, but modern cognitive theories tend to be more generous to them, influenced by the idea that our capacity for emotions is often an admirable moral adaptation. Other questions concern the cultural variability of emotion, and the dependence of some emotions, but not all, on the existence of linguistically adequate modes of expression and self-interpretation.