Causal Loops and Direct Self-Causation

ABSTRACT Causal loops are circular chains of causally related events: each link causes others which in turn cause it. Not only are causal loops widely accepted as coherently conceivable; some are also provably self-consistent as well as seeming genuinely possible according to currently accepted laws of physics. On the common assumption that causation is transitive, each link in any causal loop would wind up causing itself; but the idea of self-causation is pretty much universally rejected as incoherent. A popular attempt to resolve this dilemma distinguishes “direct” from “indirect” self-causation: the direct variety, which operates without the aid of causal intermediaries, is claimed to be impossible even if the indirect variety isn’t. I argue against this attempted resolution on the grounds that causal loops themselves, unlike the links that compose them, should be viewed as directly self-caused; so indirect self-causation via causal loop is possible only if direct self-causation is as well. An important consequence is the availability of groundbreaking solutions to several longstanding puzzles in philosophy of mind.