Look in the mirror. The face that pins you with its double gaze reveals a chastening secret.

Artificial intelligence is growing up fast, as are robots whose facial expressions can elicit empathy and make your mirror neurons quiver.

It's hard to see your own face without a mirror.

I've always loved scuba diving and the cell-tickling feel of being underwater, though it poses unique frustrations. Alone, but with others, you may share the same sights and feelings, but you can't communicate well.

On some summer days in New York City, the air hangs thickly visible, like the combined exhalations of eight million souls. Steam rising from vents underground makes you wonder if there isn't one giant sweat gland lodged beneath the city.

But remember what I said about forgetting what I said?