Thanks. But how can I even think the concept "corresponding to Earth as we know it" without relying on a large body of empirical knowledge that influences my probability assignments? I'm having trouble understanding what the prior is prior to. Of course I can refrain from explicitly calculating the K-complexity, say, of the theory in a physics textbook. But even without doing such a calculation, I still have some gut level sense of the simplicity/complexity of physics, very much based on my concrete experiences. Does that not count as anthropic?