Q: I've been having dreams where I am in someone else's dream or another person is in mine, but it's always someone I don't know. Am I actually sharing dreams with other real people or is it just a cool plot my subconscious creates? How can I know?
A: if you consider that there have-been/will-be infinite people, then they can be considered real because in an eternity of infinite possibilities, even made up things would have been real at some point