Back in Auckland, my brief was to introduce cognitive science to a department still dominated by behaviourism. My interests turned [sic] at first to mental rotation, our ability to imagine shapes rotated to different angles, and seemed to suggest that the brain may be an analogue rather than a digital device. Some of this work showed people needed to rotate a shape to its upright in order to distinguish it from its mirror image. This led back to the problem of mirror images, and why they are often hard to distinguish. It also raised to the question of why mirrors seem to reverse left and right, and not top and bottom or back and front.