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Sometimes, but not always

Another situation: when I play chess online I'm interacting with people. You can argue they're persuading me about how best to play chess, but that isn't their motive nor is there a set conclusion they're trying to make me reach

You should narrow persuasion from "interaction" to a kind of conversation (such as those found in HN threads), otherwise you could start arguing all information inputs are persuasion regardless of whether the source is human