I suggested to a friend that atheists and theists were rather similar, in that they take a position on god's existence ahead of time and argue it dogmatically, whereas philosophers are willing to evaluate the arguments and to tentatively adopt the one that they prefer for whatever reason. It's not to say that philosophers can't have a deep faith in a god or a lack thereof, but they don't see their work as defending that belief in the face of any possible objection.
But if this is true, and I think it is, how about someone who refuses to budge from what seem like moral truisms? Must a philosopher, in order to maintain integrity, put every principle on the chopping block: that if it's wrong for you to do something, all else equal, it's wrong for me to do it, or that causing people pain is wrong? Must a philosopher at least be open to the possibility that these notions are fundamentally flawed?