The emotional mind, however, takes its beliefs to be absolutely true, and so discounts any evidence to the contrary. That is why it is so hard to reason with someone who is emotionally upset: no matter the soundness of your argument from a logical point of view, it carries no weight if it is out of keeping with the emotional conviction of the moment. Feelings are self-justifying, with a set of perceptions and “proofs” all their own.
From “Emotional Intelligence”
by Daniel Goleman