In ethical discourse, valid consent is usually taken to be a necessary condition for permissible sexual activity (Archard 2007; Cahill 2001; Cowling et al. 2017; Soble et al. 2002). Since non-human animals, children, and individuals who are severely cognitively disabled, heavily intoxicated or unconscious, lack the cognitive capacity to give valid consent, this condition renders it impermissible to have sex with them. However, the claim that valid consent is necessary for permissible sexual activity seems to imply that it is also impermissible to have sex with robots, for they too are incapable of consenting because they lack the requisite cognitive capacities.
I suspect that many people find this apparent implication counterintuitive, even though they would endorse the view that valid consent is a necessary condition for permissible sex. Hence, many people seem to hold conflicting intuitions about the permissibility of non-consensual sex between cases in bouncy castle which the non-consenting subject is a robot and cases in which they are a human or non-human animal. To show that these intuitions are in fact consistent, so that neither has to be abandoned, it must be demonstrated that there is a morally significant difference between the two types of cases, which explains why valid consent is a necessary condition for permissible sexual activity if the non-consenting subject is a human or non-human animal but not when they are a robot. Solving this puzzle challenges us to refine our conception of the relation between consent and the permissibility of sexual activity, and to reflect on the ethics of robot-human interaction.
This essay proceeds in the following way. In Section 1, I elaborate on the current and anticipated design of sex robots, as well as the sex robot industry, and provide a brief overview of the ethical debate on sex robots. In section 2, I clarify the notion of valid consent, and expand on its application in sexual ethics. In section 3, I explore and reject three possible ways to argue that there is a moral difference between robots on the one hand, and humans and non-human animals on the other hand, which renders it impermissible to have non-consensual sex with the latter but not with the former. In section 4, I argue that this moral difference is grounded in a discrepancy in moral status. Section 5 concludes.