If a man who is married or in a long term relationship wants to have sexual relationships with other women, is this pathological, deviant, maybe even a disorder? Or is it part of normal and healthy male sexuality?
The issue here is 'normality' -
normal is a shifting social construct, meaning that any answer concerning
normal will be based on culture, and thus could change depending on the culture in context. A better question would be, is it adaptive or maladaptive for the person in question.
But I don't think that's what you're asking - (I could be wrong) it seems you're asking more about satisfaction of desire and whether a single partner can accomplish that.
Let me flip the question around:
If a woman who is married or in a long term relationship wants to have sexual relationships with other men, is this pathological, deviant, maybe even a disorder? Or is it part of normal and healthy female sexuality?
We can flip the gender pronouns - but in doing so, we notice an underlying assumption of male promiscuity in the original question (likely related to the idea of 'spreading seed' or a belief in a biological imperative to have as many children as possible (if this is actually true, why aren't all people constantly having children? I'm not saying it's not true; I'm saying it's much more complicated than that)).
Getting closer to an answer, let me pose more questions:
Does a happy/successful/[insert judgment function here] relationship require that both partners be satisfied in all of their desires?
-- or --
- Does a happy/successful/[insert judgment function here] relationship require that both partners learn how to control their own desires instead of being directed by them?
But that's a false dichotomy; the answer will never just be one or the other. A successful relationship will, first and foremost, involve communication. If you can communicate your desires with each other, you can both, jointly/together, pursue a sense of satisfaction (or a sense of control over that desire).
But not being able to communicate dissatisfaction is itself a sign of underlying problems in a relationship.
Biologically speaking you could say that being in a monogamous relationship is not beneficial for men, because they can't produce enough offspring. Historically and for animals, it's more beneficial to spread your genes over multiple wives, but I have not found any scientific proof that men who want to have other sexual relationships besides their own girlfriends or spouses is "normal, deviant or a disorder". Beside that, humans have been in monogamous relationships for so long now, the question should be if we still have this instinct to spread our genes as much as we can. Maybe the person in the relationship doesn't feel attracted to him or her anymore.
Attraction is also dependent on smell. In science they call that specific smell phermonones. Each person has his own kind of pheromone chemicals. The smell of these chemicals can change, for example when a woman is pregnant, ovulates or is having her period. For men these pheromones change when they are in a long-term relationships or when they are a father. You can't "smell" these pheromones consciously. The registration of these pheromones happens unconsciously.
In my opinion, either the male doesn't feel attracted to the smell of the pheromones of the female or doesn't satisfy other needs. I don't think being attracted to another female sexually is a normal part of healthy male being.
I believe most/all men will have external desires, no matter the length of the relationship. It may prove to me more so the longer you have been with one person as we are programmed as animals to spread our seed as much as we can. It does not mean you have to act on it though. I would say it is normal and healthy as long as you are not screaming out other women's names in the heat of the moment.. that would then be very healthy and could lead to amputation of your cherished member, broken objects, and divorce..
This can also be seen by the man that land extremely hot wives and run astray and fine even less attractive women to have relations with. I cannot recall the book at this moment but when I was studying PUA (long long ago) there was a book that was pretty much dedicated to how we are mammals like all others and we have the same needs and desires as the animals. I tried doing a google search but I just cannot remember the name, I think it was the Mating Mind but I could be wrong.
I am not scientist though, I am just stating my experience from talking to other males and from what I have read in books back when I was big into the PUA stuff.
Again, it is one thing to think about and desire another person, it is a completely different thing to act upon it especially when you are in a committed relationship. I would not nor have I ever cheated on my wife.