We are creatures of habit. Familiar ways of doing things in familiar contexts become automatic for us. That is to say, when we acquire a habit we can act without thinking about it at all. Habits free our minds to think about other things. Without this capacity for habitual action our daily lives would be impossible. Our minds would be crowded with innumerable mundane considerations and decisions. Habitual actions are not always mundane. Aristotle famously said that acting morally is a matter of exercising the right habits.2 For him, a lack of conscious thought is no bar on an action’s moral status. Habits are involved in our most prized activities. Of course our natural capacity for acquiring habits is sometimes a nuisance, and we acquire bad habits all too easily. But we nevertheless could not do without a vast array of habits which are not like this, and we can’t help but exercise them in our daily lives. It does not seem too strong to say that we spend much more of our time acting habitually than we do acting in the light of conscious thought. We are also rational creatures. It is because of our rationality that we naturally think that most human actions are different in kind from the behaviour of other animals. This difference is manifest in the fact that we hold rational creatures personally responsible for what they do, in ways that would make no sense for nonrational creatures. Our rationality, then, appears to give our actions a unique quality.