For a long time I have been told “ask why” in order to get deeper into someone’s mind and understand the person’s convinctions to do or believe in something. Have you ever thought about asking “how?” instead of “why?” to get this better understanding?
Most of the people you ask the “how?” question find it more difficult to put their thoughts together and to answer this specific question than to explain why they are right. They eventually realize how complex what they talked about is and may stop trying to convince you to join them. One of the possible effects of this disturbing and often unexpected question could be that they would end up believing they were going into a wrong direction… And you would not have to find any argument to convince them! Just ask them “how?” and let the magic operate.
In my life I have met a lot of people who thought they had terrific plans, ideas, projects, etc. but they had absolutely no solid argument to explain how they would do to realize them. They could talk for hours about why that’s so great but they had not thought about how they would proceed. Would you follow someone who claims he can take you somewhere but who has absolutely no idea about how he will do to succeed?
Take a look at this Business Insider article and find more links about the “how?”: http://www.businessinsider.com/how-to-win-an-argument-2014-5