Full Idea
A reversion to Aristotelian essentialism is required if quantification into modal contexts is to be insisted on. An object must be seen as having some of its traits necessarily.
Gist of Idea
Quantification into modal contexts requires objects to have an essence
Source
Willard Quine (Reference and Modality [1953], §3)
Book Reference
Quine,Willard: 'From a Logical Point of View' [Harper and Row 1963], p.155
A Reaction
This thought leads directly to Kripke's proposal of rigid designation of objects (and Lewis response of counterparts), which really gets modal logic off the ground. Quine's challenge remains - the modal logic entails a huge metaphysical commitment.