Full Idea
The subjunctive conditional depends, like indirect quotation and more so, on a dramatic projection: we feign belief in the antececent and see how convincing we then find the consequent.
Gist of Idea
We feign belief in counterfactual antecedents, and assess how convincing the consequent is
Source
Willard Quine (Word and Object [1960], §46)
Book Reference
Quine,Willard: 'Word and Object' [MIT 1969], p.222
A Reaction
This seems accurate. It means that we are only interested in when the antecedent is true, and when it is false is irrelevant.