In modem moral philosophy and in related fields such as philosophy of action and philosophy of mind, a leading idea has been that the actions, attitudes and other features of individual agents constitute the atoms in terms of which all the phenomena to be investigated should be analysed. To the problem of how individuals relate to the common, the idea of abstraction or formalisation is, in principle at least, offered as a solution. It is thought that if abstract or formal features of individual cases are found, the results will be generalizable, and to this end, suitable methods have to be worked out and employed. This programme has, during the past two hundred years or more, inspired a wealth of philosophical work which tries to shed light on who we are and how we should act and live.