>The future can never be a causal parent of the past. That's a testable statement. The reason it's testable is because we can define a hypothetical causal effe

>The future can never be a causal parent of the past. That's a testable statement. The reason it's testable is because we can define a hypothetical causal effect of the present on the past, and then do experiments and show that it's always zero. I only mean that we can talk about it, not that we can show it to be anything but a non-effect, so I'm not sure I see where we're in disagreement.