Smith earned his B.A. and M.A. in philosophy at Monash University, while his BPhil and DPhil were acquired at Oxford University under the direction of Simon Blackburn. He has held teaching appointments at various universities, including Wadham College, Oxford (1984), Monash (1984-5; 1989-94), Princeton (1985-9), and the Research School of Social Sciences, ANU (1995-2004).

In 2000, Smith's book The Moral Problem (1994) received The American Philosophical Association's first APA Book Prize for excellence in scholarship. Smith is considered to be one of the most important philosophers working in meta-ethics, and is one of the main proponents of a Neo-Humean approach to practical reason.

The moral problem

In The Moral Problem Smith diagnoses a longstanding tension between the apparent objectivity and practicality of moral judgments. The idea of moral objectivity is that "it is a distinctive feature of engaging in moral practice that the participants are concerned to get the answers to moral questions right." (1994 p. 5) Moral judgments are thought to be practical because they are thought to motivate those who accept them. But according to the Humean theory of motivation, a theory that Smith defends in chapter 4, it is not possible for a belief (a judgement about a matter of fact) to motivate someone without the presence of some antecedently held desire. Thus, if moral judgments are beliefs that motivate, they can only be beliefs about how to get something that we already want. But moral judgments, such as the judgment that murder is wrong, are not judgments about how to get something that we already want. Therefore, either they are not beliefs at all (and therefore not objective) or they cannot motivate us.

Neo-Humeanism

Hume famously claimed that reason is, and ought to be, only the slave of the passions. Humeans or Neo-Humeans do not typically hold strictly to Hume's views because, for one thing, they do not think of the passions in the same way that Hume did. Nonetheless, Humeans take their inspiration from Hume in claiming that reason alone is insufficient to motivate us to act. Often this claim is expressed in terms of beliefs and desires, and it is claimed that beliefs are mental states that are insufficient for motivation. Smith gives an analysis of action whereby in order for anything to count as an action at all, it must be explicable in terms of a belief-desire pair. He defends this account against objections by appeal to a dispositional conception of desire.

Moral realism

Smith later goes on to give an anti-Humean account of normative reasons. He thus claims to solve the moral problem by giving an account of moral judgments in terms of what one would desire if one were fully rational. As such, he attempts to maintain a form of moral realism whilst accounting for the motivational force of moral judgments.

A partial list of publications by Smith:

Books

• The Moral Problem (1994), Wiley-Blackwell.
• Ethics and the A Priori: Selected Essays on Moral Psychology and Meta-Ethics (2004), Cambridge University Press.

Articles

• "The Humean Theory of Motivation" (1987), Mind, Vol. 96, No. 381, (Jan.) pp. 36-61. JSTOR