Hi Sarah. This is one of my favorite Rand quotes.
“Reason is not automatic. Those who deny it cannot be conquered by it. Do not count on them. Leave them alone.”
Since he is an ex I am guessing reason would have been wasted on him. I think you acted perfectly and you have more proof you are better off without him.

A favorite quote of mine that is pasted on the wall in front of me at work:

"To argue with a person who has renounced the use of reason is like administering medicine to the dead."
Thomas Paine

I think you spared yourself from having an even more disgusting day.
Old dino can recall engagements with libtards.
You are called stupid and get glared and sneered at.
Nothing is accomplished.
Sometimes you get to hear a zinger, though~
One libtard told me that I supported Herman Cain because I was a racist desperate to prove that I am not a racist.

I would say you have no dog in the fight. You can't stick your neck in to another's conversations, unless you are part of it. If he is your ex, he is an ex for a reason-do not think of him.

One can always process what they are overhearing and if they choose to-find other avenues to address the arguments they overheard without engaging the person who made the comments in the first place.

ignore. . I would advise that any response would be
completely skewed by the fact that he is an "ex" and
the real subject -- Rand -- would be incidental.

are you sure that he didn't have that book, and that
he didn't make those comments, just to "get back"
at you? . I would think that any interaction would be
just a continuation of the break-up. . ignore. -- john
.

I think the key word in this is ex. There are reasons people are ex partners, and this is one of them.
"Was it right to stay silent in this circumstance?"
Yes, IMHO. People will find the truth if they seek it.

"Was this really a "betrayal", as my emotions felt like?"
You mean because you couldn't stop your ex from saying something wrong and stupid or at least refute it? I think no way. Ex-partners being stupid is normal.

"What is the best way to fight in situations like these, if at all? "
I think it depends on what you're trying to accomplish.

I'm saying b/c it's an ex be detached and ignore him, which is IMHO the right thing to but much much easier to say than to do.

Saying nothing is not betrayal. Agreeing with him to get along is and it sounds like that was not the case. As Rich pointed out, reason is not automatic and you likely would have waisted your time speaking to him.

Under the circumstances, yes. It seems there may have been another purpose than the merits of the book for your Ex to discuss the book within your earshot. Engaging him would have given your Ex a a soap box and audience.
2. No. By not responding, you didn't take the bait. Ms. Rand would have waited until the circumstances were better to her. You can see this in the behaviour of her characters in her works.
3. First determine by yourself if a "fight in situations like these" is necessary (being upset does not necessarily require a response). If so, what would you like to accomplish with the fight and does it have to be there and then. Having done this, a plan would then develop on a solid foundation.

You have coincidentally described my own personal situation exactly and accurately, except it's been going on for a while and it is getting worse. There is no way to have a rational conversation at all, so we don't. I doubt we will make it through this election cycle. My attempt to psychoanalyze myself and why I put up with this leads to despair and frustration. But something is definitely happening in the country, and I am rooting for the good guys, worthless though that action might be. Maybe.

Nothing gained by such an attempt.

"Never try to teach a pig to sing. It wastes your time and it annoys the pig."

I cannot count the number of times I have had quasi arguments with so called smart people whos eyes glaze over when confronted with logic and reason. It generally degrades to the typical liberal shout down, so why bother with them. As far a your ex, He is that for a reason, I guess I don't understand why you bother with him.

sarah,
your actions were proper. keep quiet and walk away. Even if he were just someone you knew vs an ex you would never be able to intelligently convince him of what he believed. the fact that he was reading that book should tell you that.
I am not so sure about the current partner. He should have supported you, unquestionably in this situation.

Sarah, the most important thing is that he is your "ex". Good for you! You made the right decision. You already know that any words of yours to him would be wasted.

if the attack was personal (the affair with Nat Branden) on Ayn Rand in order to discredit her philosophy, it was ad hominem and should be refuted accordingly...

Was he merely reading, or was he burbling out loud? If merely reading leave it alone unless he starts a discussion. If he's holding forth then you might want to engage him in conversation, if your silence would be interpreted as agreement. But keep in mind something that many seem to forget. What happens in a persons private life may have nothing to do with their writings, or philosophy. I personally go back to that era and I met Ayn Rand and was involved with Branden's circle of friends. It was a screwy time in which both parties were tainted. Rand, however, had a considerable circle of devotees and as the founder of the feast, was able to cast Branden out as the bad guy. With all of their brilliance and superior intellect, it just shows that people can do stupid things.

I really know too much about their personal lives to get involved disussing them. There is no question that no matter what her critics say, she is without a doubt one of the most influential writers of the 20th century, and as it looks now, perhaps the 21st century as well. Branden's books on psychology are worthy contributions to the practice and are breakthroughs in the area of the human persona via the ego. But, to answer your questions clearly:
1. Stay silent if the reader is silent.
2. It is no betrayal. You neither wrote the book nor spread the poison.
3. If it becomes verbal, and as Rand would caution, you've checked your premises, go get him, kiddo.

Those who deny reason are seen in an epistemological mirror just as are those who deny existence in the metaphysical one.

With respect to the latter, one should always take them seriously and act as if they are not there. The former, as if they are but a insignificant piece of inanimate matter.

As others have indicated, "But I don't think of you Ellsworth!" Although I know that emotionally you are likely going through your personal version of what all of us have experienced when moving ahead following discoveries that produce an "ex."

Knowing what his true motivation probably was, the best thing would have been to say, "Yeah, I've had a change of heart on all that. And, I agree with you." Then, walk away with a smile. Jerks hate that.

I wouldn't have. I would have pointed to a number of good books on Rand's actual ethics and psycho-epistemology and why it is so important for full living as a human being on this earth.

But before that I would jump hard on the notion that those that fleeced the people, and I think they were more in politics than banking, were acting on anything but what Ayn Rand taught.

Depending on my patience and what kind of rat I considered him I might or might not hang him out to try by applying his judgments to what I know of his own character. But the last would be a less useful and more personal response.

But tell me, why are you letting this person you seem to consider a creepazoid effect your day?

He's an ex. Don't worry about it.

Just a question, but unless he's been 100% faithful in his life, it's quite hypocritical to disparage someone else.

Methinks you did right by simply ignoring him. He wanted to get into an argument with you, but it wasn't over Rand.