The Kantian Thing-in-Itself as a Philosophical Fiction

Abstract

A philosophical fiction need not be philosophically useless. On the contrary, many fictive constructs are indispensable as methodological devices, and accepted as such in philosophical and scientific procedure. To see the Kantian Ding an sich as such a device is not to accuse Kant of having invented a fairy-tale. Rather, it is an attempt to understand what is involved in a philosophical method which its author himself believed to be revolutionary. It is also an attempt to rescue some of Kant's important insights from being misunderstood as merely speculative gestures. Such an attempt is not new. Its first systematic proposal was made by Hans Vaihinger, whose Philosophy of As-If 1 presented both an interpretation and a continuation of Kant, in which recognition of fictive procedure was fundamental. For Vaihinger a theoretical approach is of the as-if variety when the leading concepts employed in it are fictitious, that is to say, when they are not expected to conform or to correspond to anything given, and when confirmation of their veracity is in principle impossible. Vaihinger is perhaps a little vague on the distinction between hypothetical and as-if formulations, but in general he maintains that an ' as-if' cannot be resolved into a mere 'if'. Whilst a hypothetical assumption employs concepts in the hope of having their veracity confirmed or indirectly verified, or at least their applicability not conflicted with, attempts to provide confirmation for a fictional construct lead to contradiction. And yet such conceptual fictions can be of the greatest theoretical value. Kant certainly did not underestimate their importance. They do not serve to illuminate some kind of reality, but, in Vaihinger's words, they are instruments for finding our way about more easily in this world .2 Vaihinger was somewhat ahead of his time when he elaborated what he found in Kant and proposed it as a principle of conceptual advance. If anything makes one hesitate to give Vaihinger his due nowadays, it is the excessiveness of the claims he made for his approach. Having once recognized what he called the fictive activity of the logical function , he found fictions everywhere, and it became increasingly difficult for him to speak in any but the as-if form in the contexts of theory of science, logic, economics, sociology, jurisprudence, and even mathematics. From a sound insight into the indirect value of fictive mental constructs in the pursuit of truth, Vaihinger developed a