Conceivability and Defeasible Modal Justification

Abstract

This paper advances the thesis that we can justifiably believe philosophically interesting possibility statements. The first part of the paper critically discusses van Inwagen's skeptical arguments while at the same time laying some of the foundation for a positive view. The second part of the paper advances a view of conceivability in terms of imaginability, where imaginging can be propositional, pictorial, or a combination of the two, and argues that conceivability can, and often does, provide us with justified beliefs of what is metaphysically possible. The notion of scenarios is developed, as is an account of how filling out scenarios can uncover a defeater or, in many cases, strengthen the justification for the relevant possibility statement.

Yet another new cosmological argument

“…Grounded concepts are relevantly and ''non-accidently accurate'' and so 26 Thanks to Carrie Ichikawa Jenkins for correspondence (3/6/14) on this section of the paper. 27 See Bealer (2002), Chalmers (2002), Geirsson (2005), Gregory (2004), Jenkins (2010), Williamson (2007), and Yablo (1993). 28 See the interesting discussions of omnipotence in Rosenkrantz and Hoffman (1980, p. 14); and Hoffman and Rosenkrantz (2012, sect.…”

You Really Do Imagine It: Against Error Theories of Imagination

“…I simply want to make it plain that we can imagine impossible situations via assignments. 38 In addition to Yablo ( , 2006, explicit defenders of imagining as a guide to possibility include Chalmers (2002), Geirsson (2005), Gendler (2000b), Gregory (2004), Hart (1988), Hilll (1997, and Kung (2010). Many, many others assume it without argument, e.g., from (famously) Hume (1978) to Nagel (1974) to Lewis (1986).…”

Van Inwagen’s modal skepticism

“…That is, either it is necessary to imagine a situation that is incompatible with (and therefore rules out) :p in order to Yablo-conceive of p, or this condition isn't necessary for Yablo-conceivability. Now, if P2 is true, then this means that Yablo-conceivability is an extremely demanding imaginative exercise (as pointed out by Geirrson in a paper discussing van Inwagen's scepticism (Geirsson 2005)). So demanding, in fact, that it seems completely impractical to Yablo-conceive of propositions that we take, as part of daily life, to be obviously possible, since for (at least many of) such propositions it is extremely difficult to imagine a situation that is genuinely incompatible with the falsity of that proposition.…”