The Church-Turing Thesis, Kripke and Kant

If we consider the abundance of hypothetical and counterfactual elements embedded irrevocably in our linguistic discourse, then a possible worlds semantician might be inclined to view the existence of Kripke's rigid designators as the transcendental conditions for the consistency and intelligibility of our discourse about the world.  But here we wish to discuss a Kantian turn in a different domain. What is it exactly that it means to follow a rule, a set of rules, to play a game,  learn how to use a language, carry out a logical debate, or in general to engage in the world ? For a subject  or mind to do this, it must be computationally competent, in other words, (at least) Turing-complete.  Secondly, it must be able to do this cross-platform, in an indefinite number of domains.  Thus the Church-Turing thesis, like Kripke rigid designators, appears as a transcendental condition for the possibility of our engaging in the world. It also suggests the a priori nature of a basic but fair portion of arithmetic, combinatorics and recursion theory.