ABSTRACT
It is surely impossible to imagine how we could get by, at least in anything remotely resembling the world in which we live, without there being a place in human discussion and argument for some notion of reasonable disagreement. Although, of course, we may often think, and sometimes rightly, that those who disagree with us hold unreasonable views – we are obviously less likely to think of ourselves in this way – to a greater or lesser extent it is generally accepted that sometimes there is room for more than one view to be reasonable. The idea of reasonable disagreement may seem especially important in the context of the kind of differences and disagreements that arise in a multicultural society. Surely, the idea that we can all reasonably disagree with each other is one important, potential lubricant of such a society. As a rough starting point, by ‘reasonable disagreement’ I mean here only the very general idea that there is scope for more than one plausible or defensible belief or opinion about some matter, more than one position that can be defended with good, but less than rationally compelling, arguments or evidence. That is, we acknowledge that there is no way of showing that one view is demonstrably superior to all other views on everything about which there is disagreement. And, by implication, it is to be expected that people will sometimes disagree about some matters, without it being thought that the views of all but one of the parties must be capable of being shown to be defective in way that any reasona ble person must accept. I can still think that my view is the best, but I also accept that someone else may quite reasonably weigh the balance of arguments or evid ence differently, and thus reasonably arrive at a view other than mine. The alternatives to this scenario seem to be threefold: first, a world in which there is only one reasonable (i.e. clearly best) view about everything, all others being unreasonable; second, a world in which it is impossible to distinguish between any views in terms of their reasonableness, all views being similarly reasonable (or unreasonable); or, third, a combination of the first two altern atives, a world in which there is a sharp distinction between matters on which there is only one reasonable view and other matters on which views cannot be distinguished in terms of their reasonableness. None of these positions has much intuitive plausibility, I suggest. Although the second alternative could be pre sented as the limiting case of reasonable disagreement, it is more like a reductio
of the idea, as it would effectively undermine any point in talking about reasonable disagreement at all. For, on this view, each and every disagreement would seem to be reasonable, and any contrast between reasonable disagreement and unreasonable disagreement would be lost. So, for the notion of reasonable dis agreement to do any work, we must assume, even in this very general and vague formulation, that we sometimes have occasion to distinguish between disagree ments that we accept as reasonable and others that we do not. This very general, orienting notion, however, implies nothing about what explains how differences of view can be reasonable, about the nature of truth or the validity of scepticism, or about the extent of such reasonable disagreement, both in terms of the range of matters about which reasonable disagreement is possible and the scope for reasonable disagreement on any particular matter. I shall, though, make the, I hope, uncontroversial assumption that the range and scope of reasonable disagreement is not limited to trivial or unimportant matters, whatever these are taken to be, or to minor or insignificant differences of view. Nor does this general notion imply that the boundaries of reasonable disagree ment must be fixed or permanent, or, crucially, that there cannot be disagreement about where exactly the boundaries lie. For to say that some distinction between reasonable and unreasonable disagreements is indispensable is not to say that everyone must agree about precisely where or how that distinction is to be made (and I merely note here that this naturally gives rise to the troubling question of whether those disagreements can in turn be reasonable, a point to which I shall return later). So, in saying that some notion of reasonable disagreement is indis pensable to us in many contexts, this still leaves open a large number of ques tions about the nature, scope and explanation of such disagreements. These preliminary remarks should also make it evident that it is a vast topic that poten tially connects with questions that lie at the heart of epistemology, metaphysics and other areas of philosophy. It should come as little surprise, therefore, that my focus is much more limited. How far one can altogether avoid some of the larger and apparently intractable philosophical questions is a moot point, but I shall at least try to do so, as far as I can. Not because these philosophical questions are uninteresting; far from it. However, my concern is with the idea of reasonable disagreement as it bears on politics, focusing particularly on the role it plays in some recent liberal political theory, and generally the less that we have to invoke complex, contested and abstruse philosophical arguments the better. Even with respect to this limited area, however, I shall be highly selective; and for this reason alone, aside of several others, it should be clear from the outset that what follows cannot make any claim to comprehensiveness (whatever exactly that might mean in this context). My aim is only to shed a little light in a few dark corners and to nudge further discussion away from less illuminating areas. However, even this modest aspiration it turns out takes me into some controversial terrain.
