I once directed a production of You Can't Take It With You. My Penny never did memorize; it just wasn't important to her. She skipped a rehearsal to help her boyfriend pick out a tux for the prom. Her mother intimated that it was my fault and asked if we could delay the show so the daughter could memorize. We did not delay or cancel.Unless there are dire circumstances, don't cancel the whole production. There is a contract between a cast and the audience. We announce a show and the audience expects us to honor that commitment as best we can.If you are going the readers theatre route or have actors go on with a book in hand, recast the offending actors. If their going to read the lines anyway, get someone who may be more committed. Don't reward the bad behavior. Don't name names, but do a curtain speech that explains that do to some difficulties, some of the actors will be carrying books.I saw this at the Oregon Shakespeare Festival, where both the actor playing Romeo and his understudy were unavailable. They found a suitable actor, taught him the sword fight, and he went on. The other actors wonderfully ushered him around the stage and the audience rooted for him.On the Tuesday before a Thursday opening of West Side Story which my wife was directing, the parents of her Tony pulled him from the play. They were trying to force her to close, because they found the musical immoral. She did canceled the Thursday night performance, and opened on Friday instead. She replaced the Tony with an actor from the play. Pulled him out of classes for blocking and to memorize the lines. When other actors could get our of classes they came to help him with lines.I had to replace a Claudius in Hamlet, only two weeks before opening. He was mostly memorized. It was a modern production, so the new actor went on stage with his lines on a computer tablet which he used like a prop for his business-like character. There are ways to make it happen without canceling.Unfortunately, memorization is becoming a lost art. In a world with an eight-second attention span, the work to memorize is boring and hard. With the advent of computers, we don't have artificial intelligence, we have artificial memory. And an over-reliance on that form of memory.Whether you cancel, recast, or do reader's theatre, always ask the question, "What lesson am I teaching?" The commitment to an opening night? There are consequences to actions? The show must go on?Break all your legs.