I have been living with the same person for thirty-six years. I cannot read this man’s mind. He has anterooms in his personality I strongly suspect I have never seen. Mysteries abound. And yet time has produced an uncanny mental mirroring between us. A friend tells a story, and it triggers an immediate, identical association in each of us. Before my husband opens his mouth, I know what he will say or before I speak, he knows what I will say. The link between the heard story and our spontaneous double response is rarely obvious and why our two heads have summoned the same material at the same instant strikes us as inexplicable. It happens again and again and more and more. It may be that two minds with years of talk and grumbling and fighting and laughing and all-around bumping into each other behind them have states of mind in common. The winds rise, and the clouds begin to move, and the sun comes out at just the same time in two heads rather than one.