Power can not be wielded upon irrationalism, and where the base is emotionalism.
History has too many examples of what results. One need only turn to the Roman Republic, their emperors, daily spectacles and appeal to the people based on emotion (it was Tom Flanagan who brought this comparison between the Harper and the Con's approach to that of the politics in the Roman Republic). Our culture rejected this on moral grounds 2000 years ago. Our sciences struggled for 500 years to purge itself of this. Yet one of the most important aspects of our society, governance of this great nation, not only has not rid itself of this but I currently, with the Harper and the Con's government, in the throws of its grip. Our modern society not only does not discourage it, but the media with its never ended search for the sensational as opposed to the important, the emotional as opposed to the reasoned, distortion as opposed to truth, self-interest as opposed to the good of the people, creates fertile ground for it, encourages it and is vital in its propagation. Together they feed off each other and, if not curtailed, together they lay waist all.
Irrationalism by its very definition leads to error. Emotionalism by its very nature has no self restraint. If they sit at the seat of power, then there is no external restraint either and so they are let lose on society like the Hounds of Hell.
Irrationalism based on emotionalism requires that those that oppose are 'enemies' and so polarizes the otherwise homogeneous society into 'enemy camps'. Once again history is replete with examples of situations where these 'enemy camps' were themselves based on irrationalism, emotionally centred.
An open, free, tolerant, democratic society where information is freely, openly and undistortedly available to all, where the Rule of Law, founded on rationalism, prevails, is the basis of governance keeps these Hounds at bay.