Popper’s Three Worlds

(this is my TL;DR from Karl Popper’s Three Worlds model)

World 1: the physical world. This includes all material objects, light, magnetic fields, the universe. We all share one physical world, although each of us sees a tiny slice of it.

World 2: human experience. Feelings, emotions, the way it is to be in your head or my head. We can’t directly share this. The actions we take from here change World 1, which in turn changes our experience.

World 3: starting with language, this is everything we create in our heads and can share with other humans. Ideas, words, music, stories, recipes, concepts, memes, morals — these are objects in World 3. They are real objects; you can tell, because they have a causal effect on the world.

Blatant example: money. Not a physical object in the world. Huge causal effects that change the physical world. Money is an important part of our reality, even though it is not physical.

Books transmit stories, musical scores and recordings transmit symphonies, and printed pieces of paper transmit monetary value. We use World 1 to share World 3 objects between people. The meaning of those scratches on paper is in World 3.

The transmission isn’t perfect in either direction. It has to go through World 2, and everyone’s World 2 is different.

Thinking about reality this way helps me see why people who live quite close to me can have very different beliefs. We share some slices of World 1, but our World 3 realities are very different. Different deities are real to us, different news sources give us different facts. All this makes our experiences of life (World 2) divergent.

Reality has three parts. Physical reality is real, and it’s only the beginning.