|Geach, Peter T.
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Person/personal identity/Locke/Geach: Locke's problem can be reformulated as such: even if every human is a person and every person a human, we cannot conclude that the predicate "___ is the same person as ___" and "___ is the same human as___" fall together in use.
"Every human is a person" is equal to: "Every human is the same person as the one thing or the other"! - according to "every person is a human being" - Geach: Human and person could, according to Locke, simply diverge as different ways to count them, - Human/"surman" - identity"/Locke/Geach: to make sure, Locke assumed (erroneously) that there is no special way that an individual with a proper name had to be identical with itself. - This must be wrong, if the above is correct - because with a name, we are constantly referring to the same thing.
Logic Matters Oxford 1972