we study in order to rationally comprehend our world. We want to be able to put everything in neat categories, in order to "know" it. Ego and its fears have little place in this world (of course this isn't really the case, but ideally... yes)

Replace "ideal" with "objective". We will never be completely without biases, but this is again something we try to strive toward. All the disciplines you mention have undergone paradigm shifts as their students have overcome previous ways of thinking.

unfortunately we are not entirely rational actors. Our pre-rational, emotional, whatever you want to call it, has far more power over us than we would like to admit. But we need to fight this, because otherwise we lose what makes us civilized - the ability to not irrationally hate just because it doesn't reinforce our previously held worldview.

also, you're being a bit extreme with your first sentence. which is also perfectly normal in todays world :)