As with any other learning–and emotional intelligence is much
more amenable to training than regular intelligence–you begin by not knowing what you don’t know.
This is why the arrogance of the Left is so damaging: it makes learning and genuine, emotionally intelligent adaptation impossible.
It is astonishing to watch people who are mellow and friendly in every other aspect of their lives turn into werewolves the moment someone crosses a political line.
What this betrays, of course, is that the anger was there all along, and the veneer of kindliness and tolerance a lie. This is obvious, but I think it does lead to the reasonable claim that the Left is more of less characterized by a lack of self knowledge. I would further stipulate that the recalcitrance to introspection, and the pervasiveness of grandiose moralizing, are what make the Left–and Utopianism generally–so attractive to so many ugly people. The Left won’t ask you who you ARE. They will merely ask you what you are willing to say you believe.