There is a general belief that if you look into someones eyes you can persuade  them over to your point of view. The more you look the more persuasive you will be.   Researchers in Germany have carried out studies to show that this may only be the case if  your audience already agrees with you. Their participants were students who were assessed on the amount of  eye contact exchanged in various scenarios.

Frances Chen lead author of the study says “Eye contact is clearly used in many situations to signal attraction, love and even agreement.” Forcing  someone to look into your eyes could backfire if you’re trying to change their opinion, Chen says. “Think about parents saying, ‘Look at me when I’m talking to you!’ ”

Look Into My Eyes. Not Persuaded? You’re Not Alone. : Shots – Health News : NPR.