No one has a shorter attention span or a greater unwillingness to patiently listen and consider what you are saying than the average Evangelical Christian, for example. They are chugging thoughtlessly through a list of talking points half the time really not interested in understanding you but in spreading the Gospel . . .

Corner them intellectually. Make them thoroughly analyze and confront the total emptiness of a position and concede out loud that they have it wrong or at least that you have raised considerations they cannot answer and that they must do much more thinking on that topic, before you let them change the subject.
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