Two uses of the "Properties argument"

General form of the argument
1) Bodies have property X
2) Minds do not have property X
3) If Minds = Bodies, then they must share all properties (An instance of the "Indiscernibility of Identicals")
Therefore, Minds and Bodies are not identical

Descartes' version
1) Bodies are divisible
2) Minds are not divisible
3) If Minds = Bodies, then they must share all properties
Therefore, Minds and Bodies are not identical

Analysis of Descartes' version:
(1) seems true, and (3) is a uncontroversial principle from logic. Hence, if we want object to this argument, we should focus our attention on (2).
Objections to (2)????

Hume's version
1) Bodies have spatial position and spatial extension
2) Minds do not have spatial position and spatial extension
3) If Minds = Bodies, then they must share all properties
Therefore, Minds and Bodies are not identical

Analysis of Hume's version:
Just as in Descartes version, we need to focus our attention on (2).
What's wrong with (2)????

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