She says: “Threesomes (whether purely sexual or otherwise) can work, but the setting up of any new situation must be very carefully negotiated between all parties to avoid conflicts, jealousies, resentments and the many other problems that can arise.” I’d agree with all this.

Nice to see that there are newspaper agony aunts who are open to the idea that good relationships don’t have to be monogamous. Although she does slip up in assuming that a man with a male partner is gay…

I am using the word ‘monogamous’ in this blog to mean ‘having sex with only one person over a period of time’. A person who is monogamous is someone who, over the course of, say, a year, has sex with only one person. I will usually mean ‘sexually monogamous’, that is, if someone has a romantic attachment to more than one person but has sex with only one, they are strictly speaking being monogamous. Of course there is plenty to discuss in all this, but this definition is where I am starting from.

Helen Fisher, in Anatomy of Love: a Natural History of Monogamy Adultery and Divorce, defines the term differently, as ‘having only one spouse’ regardless of any short-term sexual relations with other people. This is more of an anthropological definition, used in discussions of forms of marriage in different cultures.

I think the definition I am using is the more widely used one in general western culture, and so will make more sense to people. Besides, we need words that distinguish people who have sex with only one person from those who have sex with more than one person.

Partner

I generally talk about partners in all my writing, rather than about husbands, wives, girlfriends or boyfriends, for two main reasons. Firstly, what I am talking about applies just as much to same-sex relationships as it does to relationships between men and women. And secondly, whether a couple is married or not is not usually relevant to the argument, as nowadays many couples live together (or even separately) without being married but the same issues surrounding monogamy still arise, just as they would if the couple were married. I am aware that ‘partner’ can mean ‘business partner’, but here it won’t mean that.

The problem with the gender-neutral approach is that you can end up with lots of ‘they’s and confusion about who is being referred to. I don’t think it is useful to use ‘he or she’ all the time, and grammatically I don’t have a problem with using ‘they’ in the singular (it is very commonly used). If you talk about a husband and a wife, you can they say ‘he did this, she said that’ and it is clear, but with two partners, ‘they did this and they did the other’ is not. I will try to make it as clear as possible, sometimes by using examples with names when no other method works. Please add a comment if a particular sentence isn’t clear to you, for this or any other reason.

Infidelity

One of the main arguments I will be making is that ‘fidelity’ shouldn’t mean the same as ‘monogamy’. For the purposes of the next few posts, however, while discussing the status quo, I will use ‘infidelity’ to mean ‘having sex with someone who isn’t your partner without your partner’s knowledge or permission’. Someone who does this could be called a ‘cheater’ and their partner has been ‘cheated on’. These terms are not ideal but I choose to use them because they are generally understood.

In mainstream British society nearly 21st century, as in many other countries today, it is expected that it person will fall in love with someone, ‘go out’ with them for a while (and not go out with anyone else during that time), and either split up or go on to marry them or at least stay together long-term.

(It is most common that these relationships are between a man and a woman, and in some circles this is the only accepted option, although in many places now same-sex relationships are also accepted. But whether same-sex or opposite-sex, it is expected that each person has only one relationship at the time.)

However, it is also widely acknowledged that people in relationships or marriages often get tempted to have sex with other people. When this happens, this is meant to be kept a secret. And if someone find out that their partner is having an affair, they are expected to be devastated, to lose faith in the cheating partner and to end the relationship.

This way of having relationships seems to be accepted by the majority of people. But is it the only way? Is everyone happy? How else could we do things?

I suggest a solution called open fidelity: a way for partners to be faithful to each other while leaving open the possibility that each of them could have other lovers or other partners at some point.