LP, the Larch Prover -- Proofs by explicit commands
The special proof method explicit-commands directs LP not to apply any
method of backward inference automatically to a conjecture, but to wait for an
explicit method to be given with a subsequent resume command. This
method is useful in several situations.
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It can be used to prevent LP from attempting to normalize a conjecture when it
would be time-consuming and unfruitful to do so. For example, if a conjecture
includes many conjuncts, it may be appropriate to first compute some critical
pairs, then apply the /\-method, and finally normalize the individual
subgoals.
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It can be used to delay the start of a proof until the user has had an
opportunity to make the conjecture immune, so that it is not reduced
once it has been proved.