ABSTRACT
The theories of conditionals from antiquity to yesterday that we have surveyed have several purposes. Some of these purposes are incompatible, and some are merely distinguishable. Possible-world theories and probability theories each have two distinguishable purposes, the evaluation of particular conditionals and the evaluation of particular conditional arguments. Earlier theories, in addition to following these pursuits, attempt to provide criteria for the logical truth of conditionals, attempt to provide a theory of deductive validity, and attempt to provide theories of inference or deducibility.
