A dissertation on the Identity of Indiscernibles

The Identity of Indiscernibles states that necessarily, if a is indiscernible from b, then a is identical with b. While this principle has fallen on hard times, the present dissertation defends it. This is accomplished by presenting new arguments for the principle and advancing two central theses. First, that the Identity of Indiscernibles is most properly interpreted from within a metaphysical context sensitive to serious questions surrounding individuals, properties, identity, and modality. When seen in such a light, the plausibility of the Identity of Indiscernibles increases dramatically. Second, I contend that by carefully distinguishing identity on the one hand from spatial considerations on the other, the Identity of Indiscernibles becomes manifestly more plausible