All parties to a reasonable conversation have to agree at the outset to set aside any trump cards their religion commends. So what if the Bible, or the Quran, says something? Since not everybody accepts that these texts are infallible, citing them as if they were is just rude.

Those who believe that their holy texts are infallible have a tough task ahead of them: convincing the rest of us, point by point, that they are right, starting from common ground.

What is common ground? In addition to the law of non-contradiction, and arithmetic, and other such universal mind-tools, there are lots of banal truths that everybody shares today: people need food to live; pain is bad (other things being equal), elephants and mice are mammals, the earth is roughly spherical, our solar system is part of the Milky Way . . . . Wherever there are factual disagreements, these can be patiently sorted out by returning to the common ground already established.

People whose religion does not permit them to engage in such open-minded discourse are in an important sense disabled: They may be the nicest people in the world, but they are incompetent participants in an open forum, and must be excused. Perhaps somebody else can be found to take on the task of representing their point of view while abiding by the basic rules of inquiry.