We care little about how our beliefs are formed, yet we are passionate about them when anyone calls them into question. Our self-esteem is threatened, not the ideas themselves.
Few spend any time and energy on analyzing how we know our most basic and valued convictions are true. In fact, we have a natural repugnance to doing so. We like to continue to believe what we have been accustomed to accept as true, and the resentment aroused when these assumptions are openly doubted leads us to seek some excuse for continuing to believe them. So most of our so-called reasoning about basic convictions is just finding arguments for continuing what we already believe.
Adapted from James Harvey Robinson, 1912