People have a tendency to just accept that infidelity is wrong but I thought it would be interesting to explore why it should be considered wrong. Now many of you are likely thinking that obviously it's wrong because it hurts your spouse/partner, it hurts their trust in you. But that just leaves the question of why does it hurt their feelings and trust? It's your body, you have every right to decide who you do and don't have sex with(assuming of course the other party is consenting) so why should a spouse or partner feel betrayed if you have sex with another person? And what gives your spouse or partner the right to demand that you have sex only with them and no one else? After all, it's your body.
Now you may bring up the idea of the risk of disease or pregnancy but with proper protection and blood tests the risks of that can be greatly minimized or even eliminated. So what other reasons could there be assuming those precautions are taken? Can it truly be said that infidelity is objectively morally wrong? And if so why?
A couple of notes: I use the term infidelity cause I can't think of a better word. Fornication doesn't quite fit cause you can do that without having multiple sexual partners. Also I put this in general debates because I want to debate this from a non-religious perspective. Obviously when religion gets involved you can come up with all kinds of reasons but I want to focus on this issue without religion.
I'm honestly confused as what part about this is unclear.
If two people agree to be sexually exclusive with each other, and one of them betrays that agreement by having sex with another person without their partner's consent, then obviously the moral problem is that one of the partners is lying to the other, and doing things they agreed not to do. A serious relationship or a marriage is about emotional connection in addition to sexual connection. It's not a recipe for a healthy partnership, where one person lies to their partner, betrays promises, doesn't respect their wishes, etc. If a partner is lying to me about stuff like that, we're done.
If, on the other hand, a couple agrees to have an open relationship, then there's nothing morally wrong with each partner having sex with other people. There's no lying or betrayal there; just doing what they said they'd do. It may or may not be an optimal situation, but it's honest. If a person doesn't ever want to be in a monogamous relationship, she should also look for partners that are okay with open relationships (non-monogamous).
A partner has every right to request whatever they want, just like their partner has every right to refuse. If my partner requests I don't play loud music at 2am in our apartment, he has every right to do it. If my partner requests I don't have sex with other people while in a sexual relationship with him (and in terms of evolution, that's likely an instinctual desire for many people), he has every right to do it. And I have every right to agree to those requests or state that they are unreasonable, and in addition I have the right to make my own requests. If we can't agree on the most important requests for us, the partnership won't work.
Yes presuming there is an agreement to monogamy made by explicitly by both parties such promises should be kept. But what if no agreement in that regard is specifically stated? Does the other member of the party have any real moral right to get upset if their partner has sex with another person?
In many if not most cultures, to seriously date or marry a person strongly implies sexual exclusivity unless stated otherwise.
Here's a quote by Richard Feynman which applies here 100%:
“By honest I don’t mean that you only tell what’s true. But you make clear the entire situation. You make clear all the information that is required for somebody else who is intelligent to make up their mind.”
In other words, being dishonest doesn't just mean telling lies. It also includes omitting facts that are probably considered important to know by the other person. If a person is in a culture where partnership strongly implies monogamy, and she has sex with another person while in a committed relationship for a reason like "because we didn't
specifically state that we wouldn't do that!", then she's playing dishonest games. If a person in a relationship is going to do something like have sex with someone outside of the relationship, she better be crystal clear that it's acceptable to her partner, otherwise she's not really respecting her partner.
To me that seems like "Good Communication 101".