This final chapter turns to the other basic question that MacCormick asked himself, again exploring it for over four decades: is reason practical, and if so how? MacCormick engaged in this question in the form of a life-long dialogue with his Enlightenment predecessors, and especially Stair, Hume, Smith, and Kant. This chapter tracks this dialogue, while also keeping in mind the contemporary interlocutors of MacCormick’s theory of practical reason, which included not only the dominant voices in Anglo–American jurisprudence, such as Hart and Dworkin, but also philosophers in the European Continent, such as Perelman and Alexy. The first part of the chapter focuses on what may be called MacCormick’s meta-ethics, showing how MacCormick adopted perspectivalism about value. The second shows how, particularly in his theory of legal reasoning, MacCormick discusses the importance of constructing an inter-subjective space (via universalisation) and how he explores the complexity of deliberation as well as the defeasibility of decision within that space. Throughout, the chapter reads MacCormick’s account of the limited practicality of reason as a matter of character.