Murphy, Nancey. Supervenience and the Nonreducibility of Ethics to Biology."
Nancey Murphy considers the role of supervenience in the relation of
evolutionary biology and ethics. She argues that God acts in the moral as well
as the biological sphere. She also challenges the attempt to reduce morality to
biology and she affirms the claim that objective moral knowledge is dependent
on a theological framework.
According to Murphy, the contemporary atomist-reductionist program can
be traced to the rise of modern science with the transition from the
Aristotelian hylomorphism to Galilean atomism. Following the success of
Newtonian mechanics, atomism was extended to chemistry. In the nineteenth
century, attempts were made to extend atomism to biology and, in our century,
to the human sphere, including psychology and a general epistemological theory
of the relations between the sciences. In this view, the world is seen as a
hierarchy of levels of complexity with a corresponding hierarchy of sciences.
Causation is strictly bottom-up from the lowest level to the top of the
hierarchy. Murphy draws on Francisco Ayalas classification and lists six types
of reductionism, including methodological reductionism which, by its success,
lends credence to the other five. Bottom-up causality and the claim that the
parts take priority over the whole embody what is, in fact, a metaphysical
assumption. Modern thought also extended atomism to areas such as political
philosophy and ethics through the writings of Thomas Hobbes and Immanuel Kant.
Still, the determinism of the laws of physics has raised problems for human
behavior. Materialists like Hobbes have simply accepted determinism, while
dualists such as Descartes have sought to avoid it, but in its place have
raised the mind-body problem, and the resulting separation of the natural and
social sciences a century later.
Murphy concludes that a proper understanding of ethics and biology will
require a thorough response to reductionism. The key will be nonreductive
physicalism, originating in the work of Roy Wood Sellars, and now including the
focus on emergent properties of hierarchical systems. Sellars, in emphasizing
the significance of organizations and wholes, opposes Cartesian dualism,
absolute idealism, and reductive materialism. Murphy then cites scientific
evidence for nonreducibility: interactions with the environment portray an
entity as part of a larger system and entail both top-down and whole-part
analyses which complement the bottom-up approach and lead to language about
emergence. The irreducibility of concepts entails the irreducibility of laws.
But how are we to explain these problems with reducibility if our analysis,
though multi-layered, still refers to one reality?
Here Murphy introduces the concept of supervenience in order to give a
non-reducible account of morality and mental events. R. M. Hare introduced the
term in 1952, and Donald Davidson developed it in 1970. It is now widely used
in philosophy, though not without disagreement. Murphys emphasis is on
circumstance: identical behavior in different circumstances could constitute
different moral judgments, and such supervenient properties are not necessarily
reducible. Then she returns to the hierarchical model of the sciences with a
branching between the human and physical sciences she and George Ellis
suggested. The human sciences are incomplete without ethics. In this scheme,
the moral supervenes on the biological if biological properties constitute
moral properties under the appropriate circumstances. She draws on Alasdair MacIntyre
and on Philip Kitchers critique of E. O. Wilson to argue that claims to reduce
ethics to biology are due to meta-ethical ignorance, challenging Richard
Alexander and Michael Ruse in passing. Instead Murphy places ethics between the
social sciences and theology. The former, rather than being value-free, now
involves moral presuppositions and ethical questions. Ethics traditionally drew
upon a concept of humankinds ultimate telos.
The Enlightenment severed the ties to this tradition but kept the same moral
prescriptions. Modern philosophers, failing to find an objective basis for
moral discourse, reduced moral claims to empirical observations. All of this is
due to our forgetting that the ought is only half of a moral truth; it is
actually connected to a telos and
a specific is statement. Murphy next discusses the supervenience relations
that obtain as we move up the scale. The predicate of virtue supervenes on
psychological characteristics, but only if there are nonreducible circumstances
related to the ultimate goals of human existence.
Murphy concludes with the relation between ethics and biology. Here we
extend the subvenience of virtues downward in the hierarchy. According to
MacIntyre, virtues are acquired and not genetically determined traits. Still
ethics will have much to learn from biology. Finally, all moral systems are
dependent for their justification on beliefs about reality. Murphy dismisses
claims like that of Jacques Monod regarding the meaningless and purposelessness
in nature. Instead, we must reject reductionism by emphasizing the top-down
connections from theology to ethics as well as the general inadequacies of
link | Printer-friendly | Feedback | Contributed by: CTNS/Vatican Observatory