Unstated assumptions that enter into thinking and writing can destroy common ground by ignoring important differences between others and ourselves. For example, a student in a religion seminar who uses we to refer to Christians and they to refer to members of other religions had better be sure that everyone in the class identifies as Christian, or some may feel left out of the discussion.
At the same time, don’t overgeneralize about or stereotype a group of people. Because stereotypes are often based on half-truths, misunderstandings, and hand-me-down prejudices, they can lead to intolerance, bias, and bigotry.
Sometimes stereotypes and assumptions lead writers to call special attention to a group affiliation when it is not relevant to the point, as in a woman plumber or a white basketball player. Even positive stereotypes—for example, Jewish doctors are the best—or neutral ones—all college students like pizza—can hurt, for they inevitably ignore the uniqueness of an individual. Careful writers make sure that their language doesn’t stereotype any group or individual.