Meaning of indiscernibility of identicals | Babel Free

Definitions

The principle that if two objects are absolutely identical then they must be indistinguishable from one another with respect to all of their properties.

Examples

“One of the fundamental principles governing identity is that of substitutivity—or, as it might well be called, that of indiscernibility of identicals. It provides that, given a true statement of identity, one of its two terms may be substituted for the other in any true statement and the result⟳ will be true.”

“For example, Levinson claims that a Stamitz symphony containing a "Manheim rocket"—a novel device in Stamitz's day—is an exciting musical work⟳, but a work⟳ written today with the same sound⟳ structure⟳ would be funny rather than exciting. Since the Stamitz symphony and the (hypothetical) contemporary sound-identical work⟳ differ⟳ in properties, it follows from the indiscernibility of identicals that they are distinct musical works.”

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