When a person purses his or her lips when you are talking, they have already formed a sentence in their mind that is in opposition to what you are saying. When you see lip pursing, you can take steps to counter their opposition before they have a chance to articulate their opposing idea. Once a person makes a public commitment, it is more difficult to change his or her mind because they must go back on something they made a public commitment to. You are more likely to change a person's mind if they do not articulate their opposition. For example, if you see your boss pursing his lips while you are presenting your proposal, you know that he has already formed a sentence in his mind in opposition to the topic you are talking about. Before the boss has a chance to say anything, you could say, "I know you must have some doubts about what I am saying, but I can assure that this concept is sound." You now have the advantage because you addressed the problem before your boss had a chance to bring it up himself. Using this technique will also make you appear to be a mind reader. This is a powerful technique for sales people to spot resistance to a sales pitch.