...the reason the have a point and defend it method is not effective is because you are guiding your audience through a justification of your point, not a realization of your point. In other words, we come to believe an idea through a series of experiences, some of them quite mystical, like hearing a song or meeting a kid or reading a book and then watching a movie. And then the light bulb went on, and we realized we should all engage fatherless kids. So when we had to give a speech about it, we jumped on wickepedia and gave some justifications for why people should engage fatherless kids. But justifications are only good after you realize an idea, not before. Justification is not how the human brain actually comes to understand an idea at all. By the end of your talk, the only people who are going to agree with you are the people who agreed with you going into it, most likely. Instead, I try to shape a talk around the way a human brain actually comes to a realization. In other words, I mimic those experiences the brain needs to encounter in order to have that “aha” moment.

Donald Miller. How I Prepare a Speech, or How to Guide Somebody Toward an Epiphany