come to be transmitted by other secondary hosts, apart from mosquitoes.
The relationally formulated ‘law’ is not really a law at all, but rather a
generalisation which lines up more-or-less usefully with the genuinely (and
non-relationally individuated) nomically connected properties.
4.4 Content in explanation: how can reasons be causes?It is deeply embedded in our common-sense, or folk, psychology that our
reasons are causes of our actions. We think we normally act as we do
becausewe believe this and desire that, orbecausewe intend to achieve the
other. But reasons, of course, are propositional attitudes with content,
partly individuated in terms of their content. A belief is always a beliefthat
P, and a desire is (arguably – there is an issue as to whether desires for
particularobjectscan always be analysed as desires for the truth of some
corresponding proposition) a desirethat Q. So when we believe that
reasons are causes we believe thatstates individuated in terms of their
contentare causes.
But now the problem for the wide-content theorist is this: if contents, in
turn, are relationally individuated, in terms of objects and properties
external to the subject, then how can the content of a mental state be a
causally relevant feature of it? For surely causation is, in general,local,
mediated by intrinsic (non-relational) properties of the events and states in
question. How can the fact that a state stands in a certain relation to
something, which may be distant from that state in space and time, be a
causally relevant feature of it, partly determining its causal powers? Ad-
mittedly, there do exist examples of relationally individuated properties
which are causally relevant. We have just discussed the causal relevance of
the relationally individuated property,being a mosquito-bite. Now con-
sider the property,being a planet. This is, plainly, a relational property: to
be a planet is to stand in a certain relation to a sun. Yet standing in that
relation is one of the determinants of the causal powers of planets. This
case is easy to understand, since the relation in question is correlated with
the existence of a causalforce(namely gravity) which acts on any planet
quamassive object. There is nothing similar to help us in connection with
widely individuated mental states. How can the mere fact that the stuVin
the lakes and rivers in my environment is composed of H 2 O rather than
XYZ, for example, make any diVerence to the causal powers of my belief
that water is wet?
Some naturalistic accounts of wide content (particularly the version of
informational semantics due to Dretske, 1988) are designed, in part, to
overcome this problem. On Dretske’s account, mental states have the
contents which they do in virtue of the information that they carry about
Explanation and causation 151