ND1irish is correct below where he says his intention is to insult because he is incapable of changing minds. He is incapable of changing minds primarily because of his approach.
I could dig up the various podcasts if interested but essentially it comes down to this:
1. Listen. Let the person you are talking to talk about their stance and their rationale for their view.
2. Find an opening for empathy. Their view is often based on a dehumanized opponent, it gets difficult to support an absolute position when confronted with an actual living breathing human that has some similarities to ones self. "Was there a time where you felt discriminated against?" or "Can you imagine having to make a choice between your own life or your baby's?"
3. Don't push, don't insult, don't belittle. Let it marinate. A change of heart often isn't instant but happens over time.
Worth noting, the one guy, and I'd have to look up his name, said that this approach worked for Gay Marriage, but not Abortion.