Start listening to him. One of two things will happen:
(a) He will talk.
(b) He will not talk.
If he talks, then there is hope. Do not interrupt him or try to correct him when he answers questions that you ask. You will ask questions in an attempt to figure out his premises. Do not be belligerent and be seriously interested and focused on what he says. Show respect. Once you fully understand where he is coming from and the intellectual constructs that support his worldview, you can begin to work at the premise level to change his mind. Undermine the core premise and then let him put the new picture together on top of that for himself.
If he does not talk, chances are his interest level in the subject is just not there. If he admits that there might be more than he first believed about these topics, he'll be facing down enormous amounts of time that have to be spent becoming educated and he'll have to do some serious mental gymnastics to concoct a new, plausible worldview based on the new information. In this case, you have to just let him be and be happy that he at least is inclined towards liberty.
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