Unless you think that biological tissue is magic, or you are a firm believer in mind-body dualism, there is little reason to doubt that a robot that is behaviourally and functionally equivalent to a human cannot sustain a meaningful relationship. There is, after all, every reason to suspect that we are programmed, by evolution and culture, to develop loving attachments to one another. It might be difficult to reverse-engineer our programming, but this is increasingly true of robots too, particularly when they are programmed with learning rules that help them to develop their own responses to the world.

The second element (ii) provides more reason to doubt the meaningfulness of robot relationships, but two points arise. First, if the real concern is that the robot serves ulterior motives and that it might betray you at some later point, then we should remember that relationships with humans are fraught with similar risks. As the philosopher Alexander Nehamas points out in On Friendship (2016), this fragility and possibility of betrayal is often what makes human relationships so valuable. Second, if the concern is about the ownership and control, then we should remember that ownership and control are socially constructed facts that can be changed if we think it morally appropriate. Humans once owned and controlled other humans but we (or at least most of us) eventually saw the moral error in this practice. We might learn to see a similar moral error in owning and controlling robots, particularly if they are behaviourally indistinguishable from human lovers.