If you wish to argue with someone, making claims about their internal state puts you totally at their mercy in a vacuum.
Outside that vacuum, it often puts them at the mercy of a mob.
Conversation
Politicians launching character assassinations from the pulpit yet being demolished by random hecklers would be a good example of the dynamic.
Replying to
Almost all of modern propaganda relies on deflection of force, because everything is cardboard and nothing can withstand a solid hit.
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