Ask HN: How to combat propaganda?
&gt;  How can you establish at least doubt in the other person&#x27;s mind?<p>Someone must be open to this in the first place. You can&#x27;t change a closed mind, and there are many reasons why a mind might be closed. They kind of have to arrive at their doubt on their own, at least in my personal non-expert opinion.  The most you can do is express your opinion in a relatively non judgmental way (because if you&#x27;re too harsh they won&#x27;t return to you later to discuss) and be available if they want to discuss.