Robin Hanson mulls the words:
In my experience “I believe X” suggests that the speaker has chosen to affiliate with X, feeling loyal to it and making it part of his or her identity. The speaker is unlikely to offer much evidence for X, or to respond to criticism of X, and such criticism will likely be seen as a personal attack.
Adam Ozimek takes this a step further:
In his post Robin argued that people often convince themselves that they truly reconsider their strongly held beliefs, but what they do is false reconsideration with the real purpose of reassuring themselves and strengthening the belief. Before it was just a strong belief, but after false reconsideration it’s a strong belief that they’ve really, definitely, seriously reconsidered. But if you can’t imagine yourself going through the day holding another set of competing beliefs than you never actually reconsidered it.
The Dish 