358 Alex Rosenberg
junction is not a causal or a real property at all. Therefore it cannot figure in an
explanation of either (PS) or (G). There are several problems with such an argu-
ment. First, the disjuncts in the disjunction ofP 1 ,∨P 2 ∨...∨Pi,∨...∨Pm,do
seem to have at least one or perhaps even two relevant properties in common: each
was selected for implementing (PS) and causally brings about the truth of (G).
Second, we need to distinguish predicates in languages from properties in objects.
It might well be that in the language employed to express biological theory, the
only predicate we employ that is true of everyPiis a disjunctive one, but it does
not follow that the property picked out by the disjunctive predicate is a disjunctive
property. Philosophy long ago learned to distinguish things from the terms we hit
upon to describe them.
How might one argue against the causal efficacy of disjunctive properties? One
might hold that disjunctive properties will be causally efficacious only when their
disjuncts subsume similar sorts of possible causal processes. If we adopt this
principle, the question at issue becomes one of whether the disjunction ofP 1 ,∨P 2 ∨
...∨Pi,∨...∨Pm subsumes similar sorts of causal processes/ The answer to
this question seems to be that the disjunction shares in common the features of
having been selected for resulting in the same outcome — PS processes. Thus, the
disjunctive predicate names a causal property, a natural kind. Antireductionists
are hard pressed to deny the truth and the explanatory power of(R).
Besides its problems in undermining putative macromolecular explanations of
(PS), (G) and what (G) explains, antireductionism faces some problems in sub-
stantiating its claims that (PS) explains (G) and (G) explains individual cases of
genetic recombination. The problems of course stem from the fact that neither
(PS) nor (G) are laws, and therefore an account is owing of how statements like
these can explain.
3 HISTORICAL REDUCTIONISMBoth the “layer-cake” reductionism of post-positivist philosophers of science and
its antireductionist rejection are irrelevant to the real issue about the relation
between non-molecular biology and molecular biology. If there is a real dispute
here, it is not about the derivability or underivability of laws in functional biology
from laws in molecular biology, as there are no laws in either subsdicipline. Nor
can the real dispute turn on the relationship between theories in molecular and
functional biology. There is only one general theory in biology, Darwinism. As
Dobzhansky recognized, it is equally indispensable to functional and molecular
biology. Once this conclusion is clear, the question of what was reductionism in
the post positivist past can be replaced by the question of what reductionism
is now. For the obsolescence of the posit-positivist model of reduction hardly
makes the question of reductionism or its denial obsolete. The accelerating pace
of developments in molecular biology makes this question is more pressing than
ever. But it is now clear that the question has to be reformulated if it is to make
contact with real issues in biology.