In the Critique of Pure Reason (1781, 1787), Kant claims to provide a proof for the PSR (principle of sufficient reason)by showing that “the PSR is the ground of possible experience, namely the objective cognition of appearances with regards to their relation in the successive series of time” (B/246/A201). Relying on his transcendental method Kant argues in the “Second Analogy of Experience” that a certain version of the PSR is a condition for the possibility of experience, and as a result also a condition for the possibility of objects of experience. Yet, this argument also restricts the validity of the PSR to human experience, i.e., to things which appear in space and time. Any use of the PSR that transgresses the boundaries of human experience is bound to generate antinomies.
... he can talk well with a sandwich in hand, which I think the earlier poster was attempting.