 Another objection to causal decision theory concedes that two-boxing is the rational choice in Newcomb’s problem but rejects causal principles of choice that yield two-boxing. It seeks noncausal principles that yield two-boxing. Positivism is a source of aversion to decision principles incorporating causation. Some decision theorists shun causation because no positivist account specifies its nature. Without a definition of causation in terms of observable phenomena, they prefer that decision theory avoid causation. Causal decision theory’s response to this objection is both to discredit positivism and also to clarify causation so that puzzles concerning it no longer give decision theory any reason to avoid it.