Die Identität des Ununterscheidbaren und die Nichtnotwendigkeit von Subjekten

Anton Friedrich Koch’s subjectivity thesis states that without embodied subjects there could be no individual things in space and time. Subjects, argues Koch, are “logico-ontologically” necessary because the problem of an apparent logical antinomy between the principle of the identity of indiscernibles and the principle of the non-generality of individuating properties can only be solved by holding that spatiotemporal individuals necessarily have indexical, hence subject-dependent, properties. This article critically examines Koch’s argument and proposes an alternative solution which, being based on individual essences, namely Plantinga’s “α-transforms” of Koch’s weakly individuating indexical properties, does not entail the necessity of subjects. The aim is to show that because of this alternative, Koch’s argument falls short of proving the subjectivity thesis ‐ if its failure is not already due to its two ‘antinomic’ main premises or to the requirements Koch imposes on any proper resolution of their conflict.