You have next to zero chance of changing someone's mind in public.

In private, I used to trip over the minefield of doublespeak which puts people into defense mode. If you can frame the discussion correctly, and if you really know your stuff, and you know exactly how much each person can handle by going slow and listening a lot.

You cannot avoid the insinuation that someone is ignorant when you are trying to change a core belief or expose someone to information that is relevant, but which they missed. It is a tightrope you walk, but it can be walked.

Tips: Find out someone's base of authority. Who do they trust? Find out their political alignment and avoid buzzwords. Don't attack individuals unless they are the topic, directly, because you might be stepping on a hero. Play on their political biases to keep the mind open. They will say, "Damn Republicans caused all this." If you think they are wrong, save it for later. One challenge at a time. Open the discussion on their side, moving in the direction you moved, when you first woke up. "The information that came out on that in 2012 was a mind-fuck. It's really hard to disregard the tin-foil nutters when..." Do not give them an opening to take a firm position. Give them plenty of openings to take the rational, "I'm an open minded individual and I'm always taking in new information" position. If you are exploring something scientific, it helps if you aren't a scientist. You need to be in a state of childlike wonder at the things you speak of. They deserve that treatment, and people LOVE to hear someone really geek out over stuff, even when they can't quite understand it. It's the, "I know it's weird that I'm so passionate about this, but YAY! I LOVE IT!!" sort of vibe. If you come across as a professor of scientist, you lose. Know how someone sees your role, and give them a reason to think that your knowledge is coincident with your specialized experience, and not your overall awesomeness. "I'm a computer guy. I'm just drawn like a fly to this stuff." Humor, if you're good at it. Personal stories. "There was a guy, once... named Raymond Rife." With this approach, you get the storyteller bonus, and there are TONS of options on this approach. Got a military man? Talk about Patton. Tell them something they don't know. Talk about Smedley Butler. EMPATHY. To be effective, you have to actually push on boundaries within these confines. If you have a great sense of empathy, you can push someone almost right up to the line where the defenses go up, and you can bring someone back from that point into full HUGGY mode... real quick. You can't ever let the defenses go up, or they don't come down.

Open the discussion expansively. If a person is wearing a mask, you have to get the mask off before you start challenging beliefs. You might not be challenging a REAL, sincere belief. You might just be running up against a person's persona. At this level, you aren't even talking to a human being... you are talking to a protective barrier.

The fact that you can't talk to someone while they are defensive means you can't be effective much or even most of the time. Choose your battles. If you are not empathetic, and you don't have a lot of experience with people, you will screw this up. That's fine. I fucked it up for about ten years.

I think it depends on the expectations you place upon your listener.

I love my girlfriend, and as part of this I, somewhat unrealistically, expect her to know the same things I do. Of course, this is not always the case when I speak about more obscure topics, and yet it always depends on my reaction (one of understanding or one of frustration) whether she becomes either receptive to, or dismissive of, learning and understanding more.

We place different levels of expectation on other friends, family and associates, but I think it's safe to say that whatever their reaction, they reflect as much about us as they do anything we say.

As you can assume by my name, yes, unfortunately.

Yeah, I talk to people about the migrant crisis and they don't give a damn even when I mention the deaths and rapes, they want to change the topic, which is fair enough it's a heavy topic.

Went on a drive to Poland a few weeks ago with someone, I have known them a long time and they are one of the topic changers. As we were passing through Calais a bunch of male "refugees" threw bottles at the windscreen and then tried to open the doors of his car, we were both shouting at them and he put his foot down and we were out of there.

All the way to Poland he was swearing them out as the scum they are. I just found it sad that the only way people will talk about a serious threat to their way of life and life itself is when they are directly faced with the threat, when often that is too far late.

Yes, they also dismiss what is being talked about as unimportant or missing the point, especially when they think there's a "bigger" issue and they aren't related.