Full Idea
The straightforward dispositional essentialist account of laws by subjunctive conditionals is false because dispositions typically suffer from finks and antidotes.
Clarification
Subjunctive conditionals say 'If x were the case..'
Gist of Idea
Essentialism can't use conditionals to explain regularities, because of possible interventions
Source
Alexander Bird (Nature's Metaphysics [2007], 3.4)
Book Reference
Bird,Alexander: 'Nature's Metaphysics' [OUP 2007], p.64
A Reaction
[Finks and antidotes intervene before a disposition can take effect] This seems very persuasive to me, and shows why you can't just explain laws as counterfactual or conditional claims. Explanation demands what underlies them.