Full Idea
Dispositionality could be what gives us the idea of there being modality in the first place: that what is might not be, and what is not could be.
Gist of Idea
Dispositions may suggest modality to us - as what might not have been, and what could have been
Source
S.Mumford/R.Lill Anjum (Getting Causes from Powers [2011], 8.5)
Book Reference
Anjum,R.J./Mumford,S.: 'Getting Causes from Powers' [OUP 2011], p.183
A Reaction
Compare Williamson's suggestion that counterfactual thinking is the source of such things, which is a similar thought. I take it to be exactly correct.
Related Ideas
Idea 14579 Dispositionality is the core modality, with possibility and necessity as its extreme cases [Mumford/Anjum]
Idea 14531 Rather than define counterfactuals using necessity, maybe necessity is a special case of counterfactuals [Williamson, by Hale/Hoffmann,A]