Counterfactuals and Modal Epistemology

Abstract

What is our epistemic access to metaphysical modality? Timothy Williamson suggests that the epistemology of counterfactuals will provide the answer. Th is paper challenges Williamson's account and argues that certain elements of the epistemology of counterfactuals that he discusses, namely so called background knowledge and constitutive facts, are already saturated with modal content which his account fails to explain. Williamson's account will fi rst be outlined and the role of background knowledge and constitutive facts analysed. Th eir key role is to restrict our imagination to rule out irrelevant counterfactual suppositions. However, background knowledge turns out to be problematic in cases where we are dealing with metaphysically possible counterfactual suppositions that violate the actual laws of physics. As we will see, unless Williamson assumes that background knowledge corresponds with the actual, true laws of physics and that these laws are metaphysically necessary, it will be diffi cult to address this problem. Furthermore, Williamson's account fails to accommodate the distinction between conceivable yet metaphysically impossible scenarios, and conceivable and metaphysically possible scenarios. Th is is because background knowledge and constitutive facts are based strictly on our knowledge of the actual world. Williamson does attempt to address this concern with regard to metaphysical necessities-as they hold across all possible worlds-but we will see that even in this case the explanation is questionable. Th ese problems, it will be suggested, cannot be addressed in a counterfactual account of the epistemology of modality. Th e paper fi nishes with an analysis of Williamson's possible rejoinders and some discussion about the prospects of an alternative account of modal epistemology.

The epistemology of modality and the problem of modal epistemic friction

“…Note that this also nicely agrees with the examples we gave: The proposition that gold E 79 is indeed metaphysically necessary, which is why (according to this criterion) it should be held fixed in a CD of any supposition (even of its negation).22 Roca-Royes (2011a, b),Tahko (2012), andCasullo (2012) have all raised this objection in alternate ways.…”

Does The Necessity of Mathematical Truths Imply Their Apriority?

“…The upshot is that there is no way to test the method or to calibrate it in the first place. We would need prior access to metaphysical necessities to enable this, but that is exactly what Williamson denies (Tahko, , p. 108).Thus, if our modal knowledge reduces to counterfactual knowledge (as per requirement (i) above), there is no reason to think it is reliable (in violation of requirement (ii) above). And, conversely, if we allow the information that would render our counterfactual judgments reliable (i.e.…”

“…The upshot is that there is no way to test the method or to calibrate it in the first place. We would need prior access to metaphysical necessities to enable this, but that is exactly what Williamson denies (Tahko, , p. 108).…”

“…To see this, consider again a key component of Williamson's methodology: we are to hold constitutive facts constant in counterfactual reasoning. Tahko () has argued that to in order to decide which are the constitutive facts, (particularly when reasoning about distant possibilities) we must be able to tell the merely physically necessary facts from the metaphysically necessary facts. But to do this, Tahko notes, requires modal knowledge.…”

An integrative design? How liberalised modal empiricism fails the integration challenge

“…Roca-Royes elsewhere criticises other modal epistemologies for also (implicitly) relying on unelucidated essentialist knowledge, see(Roca-Royes 2011a, b). See alsoTahko (2012) for an argument to the effect that Williamson's counterfactual-based modal epistemology does so, and Vaidya and Wallner (2018) raises a version of this problem for a number of prominent modal epistemologies.…”