Counterfactuals and non-exceptionalism about modal knowledge

Since our capacities and methods of cognizing reality merely seem to tell us how things are but only within close limits how they could or must be, our claims to knowledge of mere possibilities and necessities raise the suspicion of exceptionalism: the capacities and methods used in developing these claims seem special compared to those involved in cognizing reality. One may be sceptical especially with regard to them, and there are doubts that they can be naturalistically explained. To avoid exceptionalism, Timothy Williamson has proposed to reduce the epistemology of modality to the epistemology of everyday counterfactuals. There are doubts that the proposal succeeds. One objection is that the counterfactual-based epistemology fails to account for metaphysical necessities like the necessity of origin. For the account to cover such necessities, constitutive facts like the origin of a living being would have to form implicit constraints built into the capacity for everyday counterfactual reasoning. But is counterfactual reasoning indeed so constrained? I answer this question in the affirmative, presenting an epistemology of counterfactuals for modal epistemology to build on. The constraints gradually emerge by a broadly abductive process, starting from within everyday counterfactual reasoning. The process does not presuppose any independent knowledge of the constitutive status of certain facts.