Last month I read the first act of The Winter's Tale on the same day that my husband and I had an argument. I did something he had specifically asked me to do (or so I thought) and it caused a big headachy disagreement. I found myself empathizing with Hermione, who did exactly what her husband Leontes asked her to do and found that it sent him around the bend. Don't you just want to shake him, when he assumes that she's done his bidding for nefarious reasons?
Leontes is an extreme case, of course, but I think many of the most painful kinds of conflict arise when one person assumes wrongly that he knows another's intentions. It doesn't have to be "You wanted him to stay because you're having an affair with him". It can be any variation on "You did this deliberately to hurt me," from a child's assertion that his brother tripped over the Lego structure on purpose to a great-grandma's certainty that an oversight was a willful slight.
There's something so appealing about the belief that we've seen into another person's heart that I think those assumptions are particularly hard to let go of. We know what's true and we won't be dissuaded. I haven't finished the play yet but I don't imagine it will be agreeable for Leontes to realize that he's been acting like an idiot.
Today's a good day for thinking about erroneous certainty, I think, because the more we know that we're right, dernit, the harder it is to say "Be it done unto me...." I'd like to think I'd never let a misperception send me off the deep end like Leontes, but I have certainly caused damage hanging onto my own faulty assumptions. It's poison on a smaller scale, but it's poisonous nonetheless. Food for thought, on the day when we honor the one whose submission to truth crushed the serpent's head.