In my life I'm frequently regarded as a thoughtful person. This is because I like to think things over. Hence my participation in this forum.
I like to engage in a variety of ways of thinking, and my thought patterns are rarely verbal. I struggle to put my thoughts into words, typically.
This might get me classed as an npc, as my internal thoughts are less a monologue and more wordless thoughts conflicting with each other. If my thought patterns had been in words it would be a fiery debate rather than a monologue.
I have ideas and thoughts that are in strong conflict with one another. I get strong forces for and against an idea inside of me. I wonder if people notice that strong inner war, because I'll voice the result as if I'm certain things are the case that way. After, treason never succeeds. Because if treason succeeds it wasnt treason. Or in other words, the winner takes it all.
I think this idea of the NPC is just a funny popular thing. The internet flame wars thrive on making people feel insecure about things they have never thought about and the idea of their being an internal monologue or not caught on for a while.
But there is nothing in the research that suggests that these people without internal monologue have less autonomy, independant thought or are somehow more slavish towards media propaganda. It was just a funny and effective meme.
It also appeals to how people experience the world; they are at the center of every experience they have. Even if they listen to a speech, they are themselves at the center of all of their senses and thoughts. And some people that look like other people say things that sound exactly like things that have been heard before.
It's easy to think of other people as npcs.
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I don't know how it is for other people, but there is so much going on at once with thinking, that though I can observe some of it and report on it, it's like a giant orchestra, but like an orchestra that's preparing to play, one person is adjusting their instrument, another warming up their fingers, another is having a conversation.
It's only when I focus that the orchestra plays together. Programming, fighting, business talks. Especially anything competitive. Sex.