Persuasion that happens in good faith is a two-way street. You explain your position, but also truly listen to theirs. If you are prepared to change your own position based on what they say, then you can hope that they might change theirs based on what you say. If it is truly two way in this sense, including your best efforts to extract from the other party their strongest, potentially unexpected, arguments for their…
This is fine when the question is, “What’s for dinner?” However, there is nothing wrong with having core principles that aren’t able to be swayed. This is called having integrity. It’s important to understand where these lines fall within yourself and those you are speaking with. Some arguments aren’t worth having in an effort to persuade, but rather they should be discussions aimed at understanding, being vulnerable…
Well, yes there is.
In fact, that is the central problem of unresolvable divisions. People implicitly making themselves "the decider" by imagining their principles are so great as to preclude any need for revision. (Faith in the primacy of one's beliefs, is inherently the same as faith in one's own primacy to choose beliefs.)
There is nothing wrong with having strong core principles, because your best understanding supports them strongly. But as soon as you discount the possibility of them being wrong, even partially wrong, not the whole picture, framed within a non-tautological assumption, or not supercedable by other wiser principles, ..., you become the enemy of your own progress.
Nobody's knowledge, wisdom, or principles are complete, or have consistent primacy over all others.
Ultimately, principles, ethics and morality are a kind of economics. Decisions are tradeoffs between options. How does one make choices, so that the result is the outcome with the greatest value, and doesn't create other problems that exceed what is solved. That is a decidability problem, which will never have a complete or completely consistent answer.
The landscape for the question "What is best?" and "What is true?" is chaotic, fractal, non-Euclidean and infinitely complex.
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One of the biggest reasons to strong man the arguments of others, is the better at strong manning you become, the more likely you find something worth changing your own views over. Regardless of how explicit, implicit, or non-existent that was in their original argument.
Leveraging others disagreement, to identify misunderstandings and gaps in one's own knowledge, is the most important reason to talk to someone we disagree with.
Persuading them should be second, but is also more likely if we are clearly pushing ourselves to improve first.
There are very few cases where someone who disagrees with us doesn't see something wrong with our side. Or at a minimum, is not convinced because we are not as clear of a communicator as we think we are. Or not as good a listener as to what their question is, as we think. Even when we are "mostly right" and they are "mostly wrong", others rarely can't teach us something more about what we already know in one of those dimensions.
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Finally, don't try to persuade people in real time. Discuss, then move on. Discuss again if they want to.
People don't decide anything big in the moment.
They need time to understand an argument. Time to consider both its strengths and weaknesses. And time to consider ramifications we haven't even imagined. And the freedom to prioritize what is worth going down a rabbit hole for, in their life.
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I have been preparing to persuade a lot of people of something highly contrarian for a long time. This topic lights all the fires in me!