Odróżnialność a indywidualność

Abstrakt

The article considers interrelations between three philosophical issues which are relevant for the validity of the identity of indiscernibles principle: (I) different understandings of the „qualitative difference”, (II) features of space — assumptions regarding classical, commonsense and nonstandard characteristics of space, (III) objective or subjective context — assumptions concerning presence of the perceiving subject in thought experiments created to test the validity of the identity of indiscernibles principle.

Different sets of assumptions connected with those three issues are discussed and it is tested, by constructing counterexamples describing possible state of affairs, if they entail the necessary validity of the identity of indiscernibles principle. In conclusion the theses about sufficient and necessary conditions for the necessity of the identity of indiscernibles principle are stated.

Particularly it is argued that: 1) If the Principle is necessarily true then space necessarily has standard characteristics. 2) If the Principle is necessarily true then objects differ „qualitatively” even if they differ only in possessing relational properties individualized by a reference to an individual object (like being 5m from Empire State Building) 3) Only in the subjective context the Principle can hold necessarily without presupposing also a non-qualitative numerical difference. In addition some implication for the theories of individuation are pointed out. Especially it is stated that theories which postulate that object is composed only of general elements (like some versions of the bundle theory of object) can be valid only in subjective context.