 Let us explain some of the corollaries of HRT. The spatiotemporal contiguity of cause and effect excludes causation at a distance: a cause is proximate to its effect, either directly or via a chain of contiguous events (Hume 1739: book 1, part III, section II [1978: 75]). The temporal precedence of the cause and the direction of time imply that causation is asymmetric: if \(c\) causes \(e\), then it is not the case that \(e\) causes \(c\). Temporal precedence thus explains the asymmetry of causation, and how we can distinguish between cause and effect. However, it also rules out the possibility of simultaneous and backwards-in-time causation; and it dampens the prospects of a non-circular theory of time defined in terms of causation.