<i>Could Have</i> and <i>Would Have</i>

ABSTRACT An alternative to the classical Stalnaker–Lewis account of subjunctive conditionals is outlined. A distinction is drawn between a basic notion of ‘wouldness’ and a more full‐bloodedly modal variant, each with its own logic. Previous philosophers have challenged the alleged vacuity of counterpossibles using logico‐mathematically impossible worlds. Here the vacuity thesis as well as other orthodox alleged logical principles are challenged more forcefully through consideration of a logico‐mathematically possible world. The impossible‐world theorist's Strangeness of Impossibility Condition is also challenged using the same logico‐mathematically possible world. The dogma that the truth‐condition of a subjunctive invokes the antecedent worlds sufficiently ‘closest’ to (most like) the actual world is also challenged through consideration of the same logico‐mathematically possible world. The dogma is a variation on David Lewis's counterpart theory, and is flawed in the same way.