same. Conclusion: the contents of thoughts about natural kinds (and the
meanings of sentences referring to natural kinds) depend upon theactual
internal constitution of the kinds in question. Where that actual internal
constitution diVers, then so does the content of the thought. That is to say:
thought-content iswidein its individuation-conditions, involving proper-
ties (often unknown) in the thinker’s environment.
Similar arguments have been developed by Burge (1979, 1986a), in
connection with non-natural kinds, this time turning on linguistic division
of labour. (This latter phenomenon was also discovered by Putnam – I can
say ‘There is an elm in the garden’ andmeanthat it is an elm, even though I
personally cannot tell elms from beeches, because I speak with the inten-
tion of deferring to the judgements of those whocandistinguish them.)
Burge’s well-known arthritis example is designed to show that thought-
content depends for its identity partly onsocialfacts about one’s linguistic
community, which can diVer even when nothing internal to two thinkers is
diVerent. So, again, the moral is that ‘meaning ain’t in the head’.
The example (slightly adapted) is this: Petereand Petertware identical in
all physical and non-relationally described respects; and each believes that
arthritis is a painful condition aVecting the jointsand bones. The diVerence
between them is that Peterelives in a community where people use the term
‘arthritis’ just to designate a certain kind of inXammation of the joints (his
false belief results from some sort of misinformation or confusion); where-
as Petertwlives in a community where people use the term ‘arthritis’ rather
more broadly, to refer to a range of painful conditions (by hypothesis,
Petertwformed his belief through a causal route exactly mirroring the way
in which Petereformed his). But now when each of them asserts, ‘I have
arthritisin my thigh’, one of them (Petere) says somethingfalse,whereas the
other (Petertw) expresses a belief which istrue. This is then supposed to
motivate us to think that Petereand Petertwentertain beliefs with diVerent
contents, merely by virtue of living in diVerent linguistic communities. So,
it is argued, those beliefs must be externally individuated.
Yet another set of externalist intuitions is invoked by Evans (1982) and
McDowell (1984, 1986, 1994), who focus especially on singular thoughts.
They maintain that singular thoughts are bothRussellian, in that they
involve, as constituents, the actual individual things thought about, and
Fregean, in that they also involve amode of presentationof those things.
Bertrand Russell had maintained that thoughts are relations between
persons and propositions, where a proposition is a complex consisting of
the actual objects of thought themselves (individuals and properties). So if
I entertain the thought ‘Pavarotti is fat’, this consists of a relation between
me, the singer Pavarotti himself, and the property of fatness. Such a view
at least has the virtue of simplicity.
134 Content for psychology