Abstract

When, if ever, is it rational for an agent to act morally? To fully answer such a question we must appeal to a theory of practical reason. My project is to defend one such theory by determining which features we most strongly associate with practical reason and then providing a theory which best accounts for those features. ;One of the chief features we associate with practical reason is that it has to do somehow with correct deliberation. Recognizing this feature leads theorists as diverse as Hobbes and Kant to accept what might be called the standard view: it is correct deliberation, and correct deliberation alone, which reveals an agent's reasons. I argue that the most prominent and plausible examples of the standard view fail to show that there is any moral requirement that is rationally required for every given agent. ;I then argue that the inability to connect rationality and morality in this way is a severe defect of the standard view. This is because another of the chief features we associate with practical reason is that the phrase 'what is rational' is nearly synonymous with endorsing phrases such as 'what makes sense' or 'what ought to be done'. I argue that in order to preserve this synonymy we must have a theory of rationality which is capable of saying it is always irrational to violate certain moral requirements; but, this is something the standard view cannot accommodate. ;I argue that the theory which best captures the various features we associate with practical reason is the virtue theory of practical reason. It says that an agent has reason to perform an action just in case there is a suitable deliberative connection between that action and some motive she would have were she to have a correct or virtuous set of motivations. I include in the dissertation a discussion of how we gain knowledge about this set of motivations. I also address various naturalistic worries that the virtue theory raises.