Exercise:

EXISTS x(I) FORALL y(I) .P(OI) x IMPLIES Q(OI) x OR P y

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.

© 1988-99, Carnegie Mellon University.