David summarizes his distinction between inference by prediction/retrodiction and inference by measurement, and reiterates that this can make plausible the claim that the special status of the Past-Hypothesis can ground the asymmetry in our epistemic relations to the past and future. He goes through some objections to this view that came up in the class before, which he and Tim then discuss. David relates this epistemic asymmetry to the time-asymmetries in causation, counterfactual conditionals, and our apparent ability to elicit change in the world. He argues that the very facts that make the past epistemically more accessible than the future also makes our causal handle on the future far far weaker than our handle on the past. There is a discussion of how this is supposed to fit with our pre-theoretic intuition that we have NO causal handle on the past. Tim weighs in on some of these points, criticizing David's desire for a "mechanical" explanation for temporal asymmetries. He argues that our notion of a mechanical explanation already presupposes a substantive temporal asymmetry. David discusses the relation between the Mentaculus (which he takes to be the source of mechanical explanations) and the notion that time passes/has a direction. Tim responds and puts some pressure on David's claim that these two are largely independent. There is a lengthy discussion of this point.