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COUNTERFACTUALS AND TWO KINDS OF OUGHT 591
counterfactual that represents the expected value of the spinning: if one had spun, the
expected value attained would have been such and such. Since the expected value is positive,
the same goes for the embedded counterfactual. One should have spun. Ought OD and ought MR
come apart.
This reasoning is flawed: for a counterfactual to be indeterminate, it must be genuinely
contrary-to-fact: S does not obtain. For in the special case where S and R actually obtain, S
→ R is ipso facto true (by the centring axiom which forms part of the standard account used
by Hare) and not indeterminate. Yet Hare’s case is the special case. S and R do obtain. Hare
might argue that centring does not matter here: the embedded counterfactual is true iff,
judged from the closest ¬S–world, S → R is true. Yet what precludes that the actual (S-)
world outdoes any other S-world in closeness to the closest ¬S-world? Moreover, Hare’s
solution depends on rejecting a principle which many find attractive: import-export: (P →(Q
→ R)) ↔ (( P & Q) → R). Applied to the spinning wheel-example, ¬S →(S → R) leads to
the vacuous case (¬S & S) → R. The result is that the embedded counterfactual is true and
not indeterminate.
Anyway Hare’s criterion is plausible only as far as it tracks the epistemic criterion (what is in
the purview of the agent when she deliberates her action?) Disregard for the sake of argument
all my qualms about the semantics of counterfactuals. The counterfactual criterion tracks the
epistemic criterion as far as it rules out certain contingent consequences of the action under
consideration. Those consequences are known to an omniscient observer but not to the agent
deliberating her action. If all facts ruled out by counterfactually undoing the action are of this
sort, the counterfactual criterion tracks a necessary condition of ought MR .
Nevertheless the point of discerning ought MR and ought OD is missed when the real epistemic
issue is replaced by the counterfactual criterion. I use the Non-Identity problem to show this.
Hare’s solution to the new variant of the Non-Identity problem boils down to the following:
while Mary ought OD to have conceived a child earlier, Mary ought MR not. Given Mary’s Johncentred
values, from the perspective of the omniscient observer who knows that Mary will
conceive John, there is a reason for her to conceive a child earlier. For that child will be John,
and John will be valued by Mary. But Mary ought MR to have conceived a child earlier only if
the following is true:
if Mary had not acted such as to conceive a child earlier, then if Mary had acted such as
to conceive a child earlier, Mary would have conceived John.
And since the embedded counterfactual is indeterminate (there are many different possible
children which could have been the result of Mary’s action under the supposition that the
action is undone, or so I grant), the embedding counterfactual is not true but indeterminate.
It is not the case that Mary would have conceived John. Thus Mary must resort to the
expected quality of life of a child conceived earlier. Since that quality is lower than the quality
of life of a child conceived later, Mary ought MR not to have conceived a child earlier.
There are two counterarguments. Firstly, I have imagined a situation where the omniscient
being at t 1 tells Mary everything about future John. Ought MR has been introduced by reasons
within Mary’s purview. Now the reasons within Mary’s purview are the same that are within
the omniscient being’s purview. From t1 onwards, ought MR and ought OD fall together. But we
(including Mary) intuitively judge at t1 that Mary ought not to conceive a child earlier. Perfect
knowledge of John does not have to change one’s valuations. This shows that Hare’s
epistemically based distinction does not apply. But it also shows how the epistemic criterion
and the counterfactual criterion can come apart. If Hare is right about how the counterfactual
criterion works, the latter does not yield the same solution to Non-Identity as the epistemic
criterion: judging from the counterfactual criterion, Mary ought not to have conceived a child