The Temporal Asymmetry of Influence is not Statistical

We argue that the inaccessibility of the past is not merely the result of thermodynamics: instead it is a consequence of the fact that modal structure of the universe must admit only processes which cannot give rise to contradictions. We appeal to the process matrix formalism developed in the field of quantum foundations to characterise the complete set of processes which are compatible with local free will whilst ruling out contradictions. All processes known to occur in nature have causal process matrices, and a guarantee that compositions of processes will always remain causal is provided by `consistent chaining,' i.e. the requirement that the output of a process with a certain temporal orientation can only be used as the input to another process with the same temporal orientation. Since agents are also processes, agents are subject to consistent chaining requirements, with the consequence that their actions can only be used as inputs to processes with the same temporal orientation as their deliberative processes. We compare this view to the perspectival account of causation advocated by Price and Ramsey, and we discuss metaphysical pictures which are compatible with this approach, ultimately advocating a `block-process' view. Finally, we discuss the possibility that some non-causal processes may be realised in nature