Group Polarisation

I read about a study conducted by Cass Sunstein, an advisor to Obama, which has come to the conclusion that the more the people you surrounded by are ‘like minded’ and agree with your opinions, the more extreme and immune to reason your opinions will grow. The concept is known as Group Polarisation, or GP. When in a group of what amounts to sycophants, flatterers and yes men, any rare voice of disagreement will be shouted down as counter productive to the ideological direction of the group, even if such points are perfectly valid. This is how dictatorships and terrorist organisations grow as ruthless as they do. Any moderates either leave because they are uncomfortable with the actions of the hard liners, or are killed off for their differing opinions, like with what Stalin did to Trotsky. This is why you should hang on to any friendships you have with people who you often disagree with. This dissent it emerges is very good for your mental health, rationality and general level of objectiveness.