It is sometimes expedient to forget what you know.

Explanation

Discretion and prudence sometimes require setting aside what one knows — applied to situations where strict enforcement of knowledge would produce unjust or impractical results.

Where this applies

• A judge exercises discretion to exclude a piece of highly prejudicial evidence even though it is technically admissible, recognizing that sometimes it is wiser to set aside what you know.
• A prosecutor chooses not to introduce a defendant's prior conviction at sentencing because doing so would inflame the jury beyond what justice requires.
• A mediator deliberately withholds information about one party's weakness from the negotiation, judging that strict enforcement of that knowledge would derail a fair settlement.