Oxford Uehiro Prize in Practical Ethics: This requirement explains why it is impermissible to have sex with non-human animals, children, and agents with severe cognitive impairments. This paper explores the implications of this requirement for the conditions under which conjoined twins may have sex. While these implications are highly counterintuitive, it is dificult to articulate the relevant moral difference between these cases. Conjoined twinning occurs when a single embryo formed by a sperm and egg splits early in the development, but not completely.
This results in two genetically identical clones that share the same set of genes, as well as some body parts. While conjoined twins are typically classifi ed by the point of fusion, for our purposes, they may be divided into two broad categories: Permissible sexual activity is widely taken to require the valid consent of each of the participants of the sexual act. Second, consent must be given voluntarily: Third, the agent must have the capacity to consent: If any of these conditions are absent, then any resulting sexual action is non-consensual.
Given that valid consent is necessary for permissible sexual activity, let us examine cases in which consent is lacking from one twin. First, consider cases involving heterogenitally conjoined twins, such as Chang and Eng Bunker.
Consider the following case: A and B are heterogenitally conjoined twins. A validly consents to have sex with C. B does not want to have sex with C and does not give her consent. A and C go ahead and have sex anyway. Prima facie, having sex with A does not seem to entail having sex with B, given their separate genitalia.
For any two non-conjoined individuals, having sex with one of them does not entail having sex with the other. Similarly, if A and B are minimally fused, as with Chang and Eng Bunker, then it seems implausible that B and C would count as having had sex.
After all, Chang and Eng fathered a total of 21 children between them, and their descendants are considered to have come from just one of the twins. However, if A and B are more extensively fused, say through the more substantial sharing of internal organs, then B and C may well count as having sex. In such cases, the sex act would be impermissible, since the valid consent of one participant of the sex act is withheld.
This is presumably why having sex in public and exposing unwilling others to pornography is often considered to be wrong. Consequently, even if the sex is completely consensual, a moral wrong may still be committed.
Cases involving homogenitally conjoined twins, such as Abby and Brittany Hensel, are more straightforward, since having sex with one twin entails having sex with the other. A and B are homogenitally conjoined twins. A and C have sex anyway. This sexual act is impermissible for the following reasons. Furthermore, given that B does not consent to having sex with C, B and C have had non-consensual sex. This is a serious wrong and is clearly impermissible.
Consequently, on the balance of reasons, the sexual act is impermissible. The observation that having sex with someone who is a homogenitally conjoined twin entails having sex with their twin has some surprising implications. A validly consents to sex with C. A and C have sex. This sexual act is impermissible for the following reason. Sex with A is permissible only if both A and B consent to the sex act. After all, by parity of reasoning with Case 2, in virtue of having sex with A, C also has sex with B.
However, it is widely held that having sex with someone in a PVS is a serious moral wrong and so is impermissible. Such a person is not in a position to validly consent to sex, since she is not in a position to know the relevant facts about the act and so she is decisionally capacitated. Given that B is in a PVS, she is not capable of giving valid consent. Consequently, the sexual act is impermissible. This argument generalises to other cases in surprising ways.
Consider the following examples: A wants to masturbate. If A masturbates, she sexually touches B. But it seems strongly impermissible to involuntarily touch someone sexually say who is in a PVS or otherwise does not consent to being sexually touched. Consequently, A should not masturbate. A wants to donate blood.
If A donates blood, she involuntarily takes blood from B. But it seems strongly impermissible to involuntarily take the blood of someone say who is in PVS or otherwise does not consent to having their blood taken. Consequently, A should not donate blood. A has a headache and wants to take paracetamol. B does not have a headache. If A takes paracetamol, then she introduces a drug into the bloodstream of B. Consequently, A should not take the drug. A wants to undertake a risky action, which imposes upon her a non-negligible risk of serious harm.
If A undertakes this action, she also exposes B to that risk. But it seems impermissible to involuntarily expose someone say who is in PVS or otherwise does not consent to having a risk imposed on them to a non-negligible risk of serious harm. Consequently, A should not undertake the risky action. In each case, it is impermissible for A to follow her desired course of action: This generalisation poses a puzzle: Let us finish by illustrating the difficulty in driving a wedge between these cases by considering how one may argue that it could be permissible for A to masturbate.
One might invoke the doctrine of double effect to explain the asymmetry between these cases. By appealing to this doctrine, one may argue, for example, that it is permissible for A to masturbate. Even though she foresees that masturbating would entail sexually touching someone who is in a PVS, this would be an unintended consequence of her action rather than a means to bring about her pleasure.
The impermissible sexually touching is not a foreseen yet unintended side effect but the desired end in itself. However, by parity of reasoning, this entails the permissibility of having sex with conjoined twins in Case 3. After all, C has consensual sex with A, while foreseeing that this entails having non-consensual sex with B. Even though C foresees that having sex with A entails having non-consensual sex with B, he does not intend to have sex with B. This strikes me as an extremely implausible and repugnant application of the doctrine 4 of double effect, although I see no way of distinguishing between this application and the application in the previous paragraph.
Consequently, the general appeal to the doctrine of double effect fails. Unfortunately, spatial constraints prevent a thorough investigation of other potential moral differences between these cases. To conclude, this paper has argued that the actions of conjoined twins are significantly curtailed by their condition in surprising ways.
Since I have not found a satisfactory resolution to this puzzle, I leave this an open challenge for others. This author is not aware of any discussion on the relation between sexual consent and conjoined twinning. Campbell, Tim and Jeff McMahan. Cowling, Mark and Paul Reynolds, eds. Making Sense of Sexual Consent. The nature of consent. Doctrine of Double Effect. In The Stanford Encyclopedia f Philosophy, ed. Miller, Franklin and Alan Wertheimer, eds.
The Ethics of Consent: Philosophical Problems and Ethical Challenges. The Philosophy of Sex: Consent to sexual relations. I would say that if two people are sharing the same room, a very small cramped room, there are considerations they each share more-so than a large multi-room mansion.
I would lean toward the right of the one not to have sex than the one that does. The lesser damage would be done to the one wanting sex than the one that would be traumatized not wanting sex. The one not wanting sex would be frustrated at the very least and probably recover quickly. While the other could have far greater effects causing longterm mental and emotional damage.
Gum Boocho June 1, at 5: How do you know that sex is evil without consent? And if you reject the Bible as the basis, how do you know right from wrong?
You just make it up? You have no proof for the basis of your argument.