Exercise:

R(OII) a(I) b(I) AND FORALL x(I) FORALL y(I) [R x y IMPLIES R y x AND Q(OII) x y] AND FORALL u(I) FORALL v(I) [Q u v IMPLIES Q u u] IMPLIES Q a a AND Q b b

You may not use ADVICE, but all other rules and commands are allowed.

Only book theorems may be ASSERTed as lemmas without proof.

For a complete list of book theorems, type PROBLEMS.

No more help available. Sorry.

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