It goes this way...

What Freud said and neuroscience proved, only implies that human beings are prejudiced, in theory. They don't "understand" facts, instead they just try to correlate newer things, with what they already knew. Mathematically, this implies dependence of cultural biases / observations on history.

People don't work with facts, but they think they do. The acceptance of a "fact" or development of an opinion/vote is case of a dynamic equilibrium. People adjust the known facts, in effect of the environment. In general, a fact which I observed and which I think is the reason of not so successful democracies, is that people just don't have a strong opinion on anything. They are allowed to think rationally, but they seldom do; there is little role of a "fact-finding" in making of an opinion. If you present a point of view to them, they would get back with a counter-argument which in most cases, doesn't challenge the factual truth of the presented view, but just tries to attack it by evoking emotions emanating from the opposite view. The influence of this opposing argument is similarly, emotional most of the times.

Here is the average case:

A : This is observed to be this.
B: Do you mean "blah blah means blah blah blah" What about "blah blah blah"..

Most of the people who win arguments use the strategy of B. I myself have won many arguments with this strategy, but such arguments never ended with more understanding of the issue. What B does is to try to shift the opinion of A by disturbing his equilibrium of understanding (the one I talked in the very fist paragraph) Basic human tendencies of 'eye for an eye' are easy to invoke. People would shift their opinion so as to feel that they have fought back by giving counter-arguments. In this whole course of arguments and counter-arguments the truth value is buried deeper and deeper.

I don't really feel very satisfied with most of the debates I see, especially those in India, where the so-called educated élite are consequence of a colonial education system, which only teaches people to look down upon everything native.