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| Description: Law of identity
(reflexivity of class equality). Theorem 6.4 of
[Quine] p. 41.
This law is thought to have originated with Aristotle (Metaphysics, Book VII, Part 17). (Thanks to Stefan Allan for this information.) |
| Ref | Expression |
|---|---|
| eqid |
|
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | biid 168 |
. 2
| |
| 2 | 1 | eqriv 1515 |
1
|