Harris acknowledges that he is advocating a form of intolerance, but not, as he puts it, the kind of intolerance that led to the Gulag. Rather he is arguing for a conversational intolerance, one in which we examine people's convictions to see if they really scale with the available evidence. He feels that the time has come to demand intellectual honesty right across the board, and confront the prevailing taboos which, in his view, prevent us from openly criticizing religious ideas, beliefs, and practices.

Harris observes that these are essential rules which underpin progress in every other field of knowledge. He notes that we are rarely admonished simply to respect someone's views on, say, physics or history; instead, we both demand reasons and expect evidence. Anyone who fails to substantiate their viewpoint, or resents questioning, is quickly marginalized from the conversation on those topics. So Harris believes that the routine deference accorded to religious ideologies comprises a double standard which, following the events of September 11, we maintain at our peril.

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