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Another argument against the relational view is advanced by Johnston (1987:
113, 128). Exact duplicates are things sharing all their intrinsic properties,
and duplicates existing at different times are as much duplicates as duplicates
existing at the same time. But then, Johnston thinks, having a changeable
intrinsic property cannot really be bearing a relation to a time - otherwise
 duplicates existing at different times would have different intrinsics (John-
ston 1987: 113), which contradicts the original characterization of exact
duplicates.
This is anything but conclusive. For the relational theorist might just accept
that, under Johnston s definition, no exact duplicates could exist at different
times. This, of course, does not mean that things bearing exactly the same
relations to different times do not look exactly the same.
A further complaint of Johnston s (1987: 113) is that the relational theory
requires things to change their properties continuously, even if they suffer
no apparent qualitative change. A simpler way to put this point is to say that
the relational theory makes things change continuously. But this is just confu-
sion. For change is having incompatible properties or relations at different
times. Consider the canonical version of the relational theory: according to it
a banana might well bear the green-at relation to two consecutive times t and
t2 . If so, the banana bears the same relation to different consecutive times and
so it has not changed since, of course, the green-at relation is not incompatible
with itself. There is nothing in the relational theory that requires things to
bear incompatible relations to consecutive times.
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Another argument against the relational theory is Hawley s (1998: 213), which
implicitly assumes that a certain distinction between internal and external
relations is exhaustive. Thus, she argues first that changeable properties
cannot be internal relations and then that taking them to be external relations
makes them mysterious entities, and so, she thinks, the temporal parts theory
should be preferred over the relational theory.
What is wrong with the relational theory of change? 189
The distinction between internal and external relations can be drawn in
several different, but related, ways. For Hawley, internal relations are those
that supervene upon the intrinsic nature of the relata. By this she means, I
take it, that if R is an internal relation which a bears to b, then necessarily
every two things x and y with the intrinsic natures of a and b respectively are
such that x bears R to y. Provided temperatures are intrinsic properties, the
relation of being hotter than is an internal relation in this sense.
Could changeable properties be internal relations that things bear to times?
Hawley (1998: 214) thinks not, for two different reasons. Basically, her argu-
ment is that if changeable properties are taken to be internal relations to
times then one is committed not only to absolute time but also to the strange
theory that times have intrinsic properties. On the other hand, if changeable
properties of things are internal relations to times, then things have very few
intrinsic properties and it is difficult to see how the great number of a thing s
changeable properties can be accounted for in terms of those few non-change-
able intrinsic properties.
At this point, I think, someone could invoke a different notion of internal
relations, according to which entities having no intrinsic properties can enter
into internal relations provided these supervene upon the intrinsic properties
of the other relatum. But this will not help the relational theory. For although
this will be compatible with times having no intrinsic properties, we shall still
have the problem of how to account for the many changeable properties of
things in terms of a few non-changeable intrinsic properties. Perhaps then we
could resort to a notion of internal relations according to which they are those
which supervene upon the identity of the terms? This will be of no help, for it
has the awkward consequence that for all changeable properties F, if a thing
has F at t then it is essential for that thing to have F at t.
Thus, I agree with Hawley that changeable properties cannot be internal
relations to times. Can they be external relations? Hawley (1998: 215), again,
thinks not. For her external relations are those determined by or supervenient
upon the intrinsic properties of the fusion of the relata (Hawley 1998: 215).
As Hawley (1998: 215) says  [i]f the distance between an object s parts is one
of its intrinsic properties, then spatial separation is an external relation .7
Thus, supposing that there is a thing which is the fusion of the banana and
the time t at which it is green, what intrinsic property of that fusion could
determine the external relation of being green-at which the banana bears to t?
In other words, what external relations hold between the banana and t? One
might think that the answer to these questions is just the spatio-temporal
separation of the banana and t. But this, Hawley says, will not do, for such
a separation is a temporary or changeable property of the banana t fusion,
 since the banana gets closer to t, then further away, as time passes (Hawley
1998: 215). Hawley concludes that the intrinsic properties of things time
fusions that determine the changeable properties of things must be special,
permanent, non-spatio-temporal and non-causal properties of the said fusions.
What these properties are nobody knows. They are mysterious properties.
190 Gonzalo Rodriguez-Pereyra
But then, since changeable properties cannot be internal relations and taking
them to be external relations makes them mysterious entities, Hawley (1998:
215 16) concludes, the relational theory should be rejected.
Hawley s argument, if it worked, would devastate the relational theory, for
although the relational property and the instantiation versions of it do not
make properties relations they make those properties, or the having of those
properties, depend on relations which seem neither internal nor external in
Hawley s sense.
But Hawley s argument does not work. The problem with Hawley s argu-
ment is that her distinction between internal and external relations is not
exhaustive. Internal relations are those that are determined by the intrinsic
properties of the relata, whereas external ones are those determined by the
intrinsic properties of the fusions of the relata. This leaves room for rela-
tions which are determined by no intrinsic properties of anything. Couldn t
changeable properties be of this kind? Unless Hawley can give an argument
to support a negative answer to this question she has not undermined the
relational theory.8
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In his Real Time II (1998) Mellor argues against the relational theory adopted [ Pobierz całość w formacie PDF ]