“Some people believe that the age of metaphysics is past and that what metaphysicians aspire to achieve is an impossible dream. They claim that it is an illusion to suppose that human beings can formulate and justify an undistorted picture of the fundamental structure of reality — either because reality is inaccessible to us or else because it is a myth to suppose that a reality independent of our beliefs exists at all. To these sceptics I reply that the pursuit of metaphysics is inescapable for any rational being and that they themselves demonstrate this in the objections which they raise against it. For to say that reality is inaccessible to us or that there is no reality independent of our beliefs is just to make a metaphysical claim.
And if they reply by admitting this while at the same time denying that they or any one else can justify metaphysical claims by reasoned argument, then my response is twofold. First, unless they can give me some reason for thinking that metaphysical claims are never justifiable, I do not see why I should accept what they say about this. Secondly, if they mean to abandon reasoned argument altogether, even in defence of their own position, then I have nothing to say to them because they have excluded themselves from further debate.”