Kant is well known for taking seriously the lack of justification for induction voiced by Hume and finding what is left for us to be able to know and believe. I wonder, with the knowledge that the same lack of justification holds for deduction (see: Haack, S. (1976). The justification of deduction. Mind, 85(337), 112-119.), whether there has been any philosopher (perhaps a neo-Kantian) that undertook something similar to Kant with this added lack of justification.