Katarzyna
Lazari-Radek and Peter Singer’s paper “The Objectivity of Ethics and the Unity
of Practical Reason”, published in Ethics
123 (2012): 9-31, aims to defend the objectivity of ethics, or more precisely
the objectivity of a particular ethical judgement, against the kind of
evolutionary debunking argument that was brought forward especially by Sharon
Street.[1]
They take as their starting point the “dualism of practical reason” that
confounded Henry Sidgwick in his Methods
of Ethics[2]
and that prevented him from concluding that there is only one rational answer
to the question what we ought to do, namely the utilitarian one that favours
impartiality and tells us to aim at the good of all. Sidgwick’s problem was
that it seems just as rational to only aim at one’s own good. Thus practical
reason commands us to both pursue our
own best interest and the best
interest of all. Although those two goals may often coincide, there are clearly
also situations where they can clash. Therefore, in those situations, reason
cannot tell us what we ought to do. Sidgwick thought that this problem could
not be resolved and that, therefore, ethics cannot be completely rationalized.
Lazari-Radek and Singer think it can.
Their
strategy is to revisit Street’s evolutionary critique of objectivity in ethics
and then to show that while the maxim of universal benevolence or impartiality
survives the attack, rational egoism does not. Street has argued that our
evaluative attitudes including our moral beliefs about what is right and wrong
have been shaped by evolutionary forces and that because our knowledge of how
evolution works gives us no reason to suppose that it favours the development
of evaluative attitudes that are objectively true (rather than beliefs that are
conducive to our survival and to reproductive success), it would be a very
unlikely coincidence if our moral beliefs actually were all true. If we were
constructed in a different way (say, more like social insects), so that our
survival and reproductive success were dependent on different evaluative
attitudes, then we would think differently about what is right and wrong.
Hence, we have no reason to suppose that our moral beliefs are objectively
true.
However,
Lazari-Radek & Singer argue that while this argument is on the whole
persuasive, it does not undermine the
objective truth of the ultimate
principle of ethics, which, with Sidgwick, they take to be the principle that
we should always do “what is best for the well-being of all” (16), precisely
because such a principle does not
seem to improve our chances of survival or to increase our reproductive
success. On the contrary, it seems to diminish it (19-21).
Indeed,
if believing in the objective truth of that principle were conducive to our survival or reproductive success, then we
would have no good reason to suppose that the principle was objectively true.
But if it is in fact not conducive to
our survival or well-being, then, paradoxically we do have a reason to regard the belief as objectively true. Why is
that? Because if that belief does not stem from our evolved evaluative
attitudes, then it can only be the result of the use of reason. Of course our ability to reason generally is very useful
for us by allowing us to solve problems that would otherwise have threatened
our survival, so it no doubt has evolutionary value, too, but it is quite
possible that it also allows us to do
things that are not relevant to our survival, like doing advanced physics and
mathematics and grasping objective moral truths. So when we ask why we
developed those particular abilities in the first place if they are not
conducive to our survival, then a plausible explanation for their existence is
“that the ability to reason comes as a package that could not be economically
divided by evolutionary pressures. Either we have a capacity to reason that
includes the capacity to do advanced physics and mathematics and to grasp
objective moral truths, or we have a much more limited capacity to reason that
lacks not only these abilities but others that confer an overriding
evolutionary advantage. If reason is a unity of this kind, having the package
would have been more conducive to survival and reproduction than not having
it.” (17)
The
unity of reason helps us explain why we have the ability to track moral truths
despite the fact that we could survive and reproduce just as well, or even
better, without it, and this lack of
an evolutionary explanation allows us to conclude that the principle of
universal benevolence must be objectively true: “there is no plausible
explanation of this principle as the direct outcome of an evolutionary process,
nor is there any other obvious non-truth-tracking explanation.” (26)
For
the same reason we can now also conclude that practical egoism, i.e. the maxim
that we should always choose the action that produces the best outcome for ourselves, is not objectively true. We do, after all, have a perfectly good
evolutionary explanation for why we should have that particular evaluative
attitude. The belief that we primarily ought to promote our own good and that
of our kin rather than that of everyone is exactly the kind of evaluative
attitude that we should expect to have developed under evolutionary pressures.
It is therefore not reliable and should not be seen as having any normative
significance. Since we have that attitude not because we have used our ability
to reason and as a result grasped the truth of the underlying principle of
egoism, but merely because we have been shaped by the forces of evolution to be
that way, practical egoism is in fact not
rational. Sidgwick’s dualism of practical reason is thus proven to be
unfounded. There is no dualism of practical reason. What practical reason
commands is one thing, and one thing only: that we always seek and promote the
best outcome for all (28).
Is
that argument convincing? I think not. While it may make sense to distrust
beliefs and evaluative attitudes that we merely have because having them
increases (or at one point did increase) our evolutionary fitness (so that we
can assume we would also have them if they were not true) and to try and
confirm them on independent grounds, this gives us no reason at all not to hold
on to those beliefs and attitudes. It merely gives us reason to doubt that
those attitudes are objectively true.
If I have to have a healthy concern for my own good to survive, and I do have
an interest in surviving, then it is perfectly rational for me to promote my
own good first and foremost. It is just not rational to believe that this is
what I ought to do, or more precisely
that it is objectively true that this is what I ought to do. In other words, it
is difficult to uphold moral realism
in the face of an evolutionary explanation of our moral beliefs, but it is not
difficult to continue letting ourselves be guided by certain moral or
prudential principles.
Perhaps
more importantly in the context of the present argument, the fact that we do not have an evolutionary explanation for
some of our evaluative attitudes, e.g. universal benevolence or the belief that
we should do what is best for all, does not imply that they are more reliable
than those that can be thus explained.
When Lazari-Radek and Singer state that “there is no plausible
explanation of this principle as the direct outcome of an evolutionary process,
nor is there any other obvious non-truth-tracking explanation” (26), they
simply assume without further argument that those acts of reasoning that lead
us (or some of us) to postulate that particular moral principle of universal
benevolence are truth-tracking. But
surely the fact that a belief is not directly caused by evolutionary forces
does not prove that we have it because it is true. If reason comes indeed in
one package, so that our ability to postulate the truth of that particular
moral principle is a mere (not fitness-enhancing) by-product or our (generally
fitness-enhancing) ability to reason, then we have already explained it. A further
explanation – we have it because that belief is true – is not needed. Moreover,
it is difficult to see why we should assume that, although reason is generally
an ability that has evolved because it increases our chances of survival and
not because it leads us to the truth, should in some instances allow us to see the world as it really is. If reason
is not generally truth-tracking, why
should we suppose that it is when it leads us to have beliefs that are not
conducive to our survival? The hypothesis of a “unity of reason” helps us
explain how we could have developed
an ability to grasp objective moral truths, just as it helps us explain why we
have developed the ability to grasp abstract mathematical truths that have no
practical value, but it doesn’t do anything to show that we have indeed
developed such an ability.
