If you never leave your house, you’ll never know what the outside looks like.
One idea that holds a lot of explanatory power for me is the distinction between people as they really are and the mental models we have of people.
Whether it’s someone you encounter on the street for 30 seconds or someone you’ve known intimately for a decade, when you deal with that person, you’re really dealing with your mental model of that person. Some models are more accurate than others, of course, and in the process of getting to know someone, you refine your model of that person.
But the assumption that there is any such thing as the “person as you really are” raises an interesting epistemological issue. Anyone with a modicum of honesty and self-knowledge will admit that he does not have a perfectly objective self-assessment. And no other person could believably claim to have a better assessment of a person than the person himself. So that leaves the person’s true nature in a position akin to that of Schredinger’s cat, but in a box that’s been permanently locked shut.
The physics metaphor seems prone to over-stretching, so here’s another one: the self is like a house. You’re born in that house and you never have a chance to leave it, that is, you never get to look at yourself with another person’s eyes (I’m going to arbitrarily assert that drugs, “astral travel” and suchlike mystical claptrap don’t count). So you have no idea what the outside looks like. But you know every damn crack and crevice, every squeaky floorboard, and the right way to hike the key in the back door to get the lock to turn. Other people are on the outside looking in. Some people press their noses right up against the windows and get a pretty good idea of the house’s floor plan, but can never feel what it’s like to live in that house.
And perhaps most importantly, nobody has any idea what the structure and mechanical systems of the house looks like, hidden inside the walls. Are the wall studs 16″ on-center, or did the contractor skimp and use 24″ on-center? Is the plumbing copper or PVC? That’s a three-prong outlet there, but is it really grounded?
Perhaps if you believe in God, you can tell yourself that God knows. But I don’t.