Full Idea
The third, more recent, approach to reduction is a modal matter. A class of propositions will reduce to - or supervene upon - another if, necessarily, any truth from the one is entailed by truths from the other.
Gist of Idea
Reduction is modal, if the reductions necessarily entail the truth of the target sentence
Source
Kit Fine (The Question of Realism [2001], 3)
Book Reference
-: 'Philosophers' Imprint' [-], p.10
A Reaction
[He cites Armstrong, Chalmers and Jackson for this approach] Fine notes that some people reject supervenience as a sort of reduction. He objects that this reduction doesn't necessarily lead to something more basic.