Caring, it turns out, is less about what you say than what you are willing to hand over. One of the AZR-0 robots has taken this about as far as it can go, offering a companion its own arm, freely and without ceremony, as though it were the most natural thing in the world. There is something disarming about a gift like that, pun entirely intended. The creatures we designed seem to grasp what takes most of us years to learn: that real care means giving the thing that costs you something, and making no fuss about it at all.