In the previous chapters, I have argued that we must clearly separate the task of justifying liberal political principles from that of motivating persons to act in accordance with them. Recognizing this difference helps us to avoid thinking that the mere fact that those principles are justified will assure that citizens will be motivated to act in accordance with them.

In particular, I have argued that we cannot rely on individuals to be moved to act as good liberals merely through the exercise of their rational faculties. Conceived of instrumentally, reason is represented as attaching to the “engine” of desire, directing and channeling the passions in an efficient – but not necessarily liberal – direction. Thought of in an absolute sense, rationality can be defined in a way that links it to liberal values. Doing this, however, effectively cuts off rationality from an individual's desires; the rational individual will be liberal, but there is no special motivation for anyone to be rational.

In claiming this, I do not intend to deny reason its essential role in liberalism, but rather to underscore one basic point: For reason to lead to actions that are consistent with liberal principles, it must operate in the right kind of context of values. The central challenge facing those who want to develop and sustain liberal institutions, then, is not simply to develop what we might call the “rational faculties” of individuals – the ability to weigh reasons and evidence and think abstractly – but also to create and maintain the aims and values appropriate for liberalism.