Abstract

It is necessary to reconsider P. M. S. Hacker’s assessment of Kant and Wittgenstein’s philosophical affinities and the question concerning Wittgenstein’s alleged use of “transcendental arguments”. First, Alfred Norman’s reading of the Tractatus Logico-Philosophicus as a thought experiment receives revision to develop a view of the Critique of Pure Reason as a large-scale thought experiment that shares important logical features with the Tractatus. Then the question is addressed whether the middle Wittgenstein and the pre-critical Kant employed any thought experiments that could be equally characterised as “transcendental arguments”. A rational reconstruction of both thinkers’ arguments is carried out in the light of the contemporary literature on thought experimenting. The novelty and relevance of this approach is the emphasis laid upon a largely neglected affinity between Kant and Wittgenstein, namely the systematic use of thought experiments in their epistemological pursuits. The conclusions are: i) Wittgenstein’s and Kant’s magna opera can be seen as philosophical thought experiments that attempt to try out the limits of language and the limits of possible experience respectively; ii) Both philosophers developed arguments that can be designated as transcendental if only from a methodological standpoint; and iii) some key arguments put forward by the middle Wittgenstein in the determination of the structure of visual space could be characterised better as thought experiments than transcendental arguments.