Logic and Liberalism

Abstract

What does it take for a society to become enlightened? Kant suggests that the members of it must be free to use their ‘public reason’. Arendt develops this thought, adding that we must be able to recognize the others in our society as worthy of intellectual engagement. But, what happens when we disagree in extreme ways, for example about the laws of logic? On some traditional conceptions of the connection between logic and rationality, disagreements of this kind force us to regard others in our society as irrational. In this paper, I argue that, if we want to maintain a Kantian model of enlightenment, then these kinds of disagreements push us towards a logical pluralism. I examine two forms of pluralism, Beall and Restall’s, and Carnap’s, and show that Beall and Restall’s version conceals a lurking monism, and so cannot be the kind of pluralism needed for enlightenment. But, I argue that Carnap’s pluralism is. I conclude by examining the history of Carnap’s pluralism, and show that using it for political ends – namely, for facilitating discussion in pursuit of enlightenment – is consistent with Carnap’s initial motivations for his work, and clears the way back towards Kantian enlightenment.