How do you justify learning something about the universe or society from somebody else, which your imagination would not have singlehandedly known or guessed at, which then turns out to be true?
There’s proof that others tangibly exist. How do you prove everyone else has a consciousness and mind? Well, the internet proves not everyone does, but the fact that this question arises in philosophy at all confirms that others had to have thought of this principle first; as demonstrated by the previous factoid.
