How do you judge the plausibility of a counterfactual?
You say “we can imagine” some of these scenarios more easily than others. But our imaginations aren’t magic. There are plenty of things I can imagine that on closer examination are virtually impossible. And plenty of real things that I couldn’t imagine until I knew about them.
If we had a good causal model, we could apply it. But we’re usually interested in non-causal models precisely when causal models are intractable.
If the counterfactuals’ plausibilities boil down to “I said so”, then so does the entire argument.
1) model M claims that X happened necessarily the way it did, for reasons we don’t understand.
2) A critic presents a counterfactual C where X doesn’t happen that way, while C is still consistent with the model. To argue that C changes X, he uses causal reasoning.
3) The defenders of the model must now either abandon the model, show that C is not actually consistent with M, or refute the claim that C changes X.
4) The conversation has now progressed beyond direct claims of likelyhood or not of M.
If the counterfactuals’ plausibilities boil down to “I said so”, then so does the entire argument.
It depends what kind of argument is being made via presenting the counterfactual. If it is challenging the generalisability of a strategy (like a moral system or a decision theory) then an implausible counterfactual is just what is needed. Plausibility would be a distraction.
How do you judge the plausibility of a counterfactual?
You say “we can imagine” some of these scenarios more easily than others. But our imaginations aren’t magic. There are plenty of things I can imagine that on closer examination are virtually impossible. And plenty of real things that I couldn’t imagine until I knew about them.
If we had a good causal model, we could apply it. But we’re usually interested in non-causal models precisely when causal models are intractable.
If the counterfactuals’ plausibilities boil down to “I said so”, then so does the entire argument.
Schematically:
1) model M claims that X happened necessarily the way it did, for reasons we don’t understand.
2) A critic presents a counterfactual C where X doesn’t happen that way, while C is still consistent with the model. To argue that C changes X, he uses causal reasoning.
3) The defenders of the model must now either abandon the model, show that C is not actually consistent with M, or refute the claim that C changes X.
4) The conversation has now progressed beyond direct claims of likelyhood or not of M.
It depends what kind of argument is being made via presenting the counterfactual. If it is challenging the generalisability of a strategy (like a moral system or a decision theory) then an implausible counterfactual is just what is needed. Plausibility would be a distraction.