(2) Morality requires us to be motivated to act in moral ways and to act on those motives
in the appropriate circumstances. Many moral acts also aim at producing particular
outcomes.
(3) No one can be required to engage in an activity if he reasonably judges that he is
taking a risk that it is pointless or self-defeating and is unable to judge the degree of the
risk.^8
(4) The moral life requires some degree of confidence that the effort to be moral is not
pointless or self-defeating.
(5) Trust in the general truth of our moral beliefs (or at least, our ability to
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find out whether they are true), the accuracy of our motivational states (our emotions fit
the circumstances, what we desire is desirable, etc.), and our probable success in reaching
moral outcomes is a condition for confidence that the effort to be moral is not pointless or
self-defeating.
(6) On the radical skeptical hypotheses we cannot have any confidence in the truth of our
moral beliefs, the trustworthiness of our motivational states, or our probable success in
reaching moral outcomes. On the radical skeptical hypotheses the effort to be moral, for
all we know, may be pointless or self-defeating.
(7) Hence, morality does not obligate us unless we have reason to believe that the
skeptical hypotheses are false. Moral obligation requires that there be a guarantor of our
trust in our moral beliefs, motives, and success in action. As Kant puts it, we must
suppose the existence of a cause adequate to the effect: a Providential God.
Notice that according to this argument, our motive for being moral is not threatened as
long as we believe there is a God, but morality does not actually obligate us unless the
belief is true. If that is the case, then this argument may be able to avoid a well-known
objection to Kant's transcendental argument against belief skepticism. The problem
sometimes raised against the latter argument is that it shows us how we have to think, not
how things have to be. Even if we have to make judgments about an outer world in order
to make judgments about the existence of our own minds, it does not follow that the
judgments in either category must be true. As long as there is no requirement that the way
we think lines up with the way things are, we have not escaped skepticism. I will not
discuss the merits of this objection, although I think it is a powerful one. What I want to
point out is that the objection cannot so easily be raised against the argument above
because there is a requirement that our moral motives line up with moral reality. In fact,
morality just is the demand that that be so. Morality requires the falsehood of both belief
skepticism, and motivation skepticism and moral motivation requires a guarantor of that
falsehood. A deity may not be the only metaphysically adequate guarantor, but in the
absence of competitors, he is the most obvious choice to fit the role.
The above argument assumes a form of moral realism, the theory that there are moral
facts independent of human perceptions and attitudes, since it presupposes that moral
obligation has a source outside of the human mind. Moral skepticism, like skepticism
about perception and belief, is most threatening within a realist metaphysics, and so
idealism (antirealism) is a possible solution. I think it is no accident that the popularity of
antirealism in ethics coincides with the decline in belief in a theistic foundation for