Asked without prejudice.

Don't hang up on 'em; G_d forbid, don't!

So what do you do?

What do you do when they start hurling abuse? I'm not talking about elevated blood pressure, its attendant vitupritive. I'm talking about out-and-out nasty, words meant for vicious, without redeeming social value.

Amazingly, no matter what's being said at the other end, it seems it's worse to end it in the cradle. Not the abuse, but the ending of it that puts an end to friendship, collaboration...?

What do you think?

Was this a Reply to something?

If not, then I don't answer them in the first place.

Dear IP:" out-and-out nasty, words meant for vicious, without redeeming social value."

I sounds as though you are talking about nasty people on telephone. When I could still hear, I used to hang up at first nasty word, unless it was my boss. Courtesy is wasted on nasty people.

Well, Sweetie, there are a number of things that I would do,
depending mostly I guess on who the caller was. I am basing all these on the assumption that it is someone whom I would prefer to maintain contact with. My first
reaction would be to want to hang up and send them a note
saying I would be willing to listen to their concerns when I could be allowed to think of a calm, rational response and not be distracted by the loudness and cursing (if applicable). This is designed to have the same effect as
saying, "when you can be rational", but does not imply judgment of them. When someone feels judged, that's probably the mostly likely thing they're going to base their response on, no matter what the main point of your statement was. After all, the goal (in this instance) is to get them to change their behavior, and setting them off again will not acheive that goal.

Now--the hang-up and send a message method would not be my first choice if I had more investment in maintaining the relationship than they did. (Say, the deal would fall through, or I would lose a long-time friendship.) In this case, I would probably lay the receiver down until the
squawking stopped, then pick it up and ask if they were willing to let me say something. I would probably begin by
telling them that they and their concerns are important to me, and let that sink into a couple seconds of silence.
Then I would probably apologize--do say this first, it can
be disarming--for not being able to get {whichever fits}
their main point, or if I did get the main point of their
argument, their reasons behind it, and would they please
re-state them. If I have in fact managed to catch anything of what their point is, I would re-state that and ask them to clarify whether I got it accurately.

Now--the above would really depend on my judgment of the person at the time: are they normally a rational person who is likely to be lured into the logistics of listing their grievances, and is just really upset about this one thing? If it is someone for whom irrational irateness is a
normal way of behaving, this will not work!

If it is the latter type of person, and you need or want to maintain contact, then you may just have to put up with the abuse. If there is an opportunity to bring it up when they seem willing to really hear you, you might try saying something like, "I really have a hard time when you yell and curse. In amongst all that, I tend to lose track of what your point is." (Again, not judging them yet still aiming towards getting them to change their behavior.) Don't ask, even non-verbally, for them to agree to this
thinly-veiled request. Just let it fall into silence. If they are determined to maintain one-up-man-ship, they will perceive a request like this as a challenge to their alleged superiority, and will respond by renewing efforts to demonstrate this "superiority", rather than visibly accede to the wishes of someone they consider inferior.

Please note: I am not acknowledging the "superior/inferior"
rankings as being true: just that there are some people who perceive things this way.