possible that there was only a fairly limited mind-reading capacity in
existence prior to the evolution of language; and that language and a
capacity for structured HOTs co-evolved (see Gomez, 1998, for an account
of this sort). Even if this were so, however, it would remain an open
question whether language would be implicated in the internal operations
of the mature mind-reading faculty. Even if they co-evolved, it may well be
that structured HOTs are possible for contemporary individuals in the
absence of language.
In so far as there is evidence bearing on this issue, it supports the view
that structured HOTs can be entertained independently of natural lan-
guage. One sort of evidence relates to those deaf people who grow up
isolated from deaf communities, and who do not learn any form of
syntactically structured Sign until quite late (Sachs, 1989; Goldin-Meadow
and Mylander, 1990; Schaller, 1991). These people nevertheless devise
systems of ‘home-sign’ of their own, and often engage in elaborate pan-
tomimes to communicate their meaning. These seem like classic cases of
Gricean communication; and they seem to presuppose that a capacity for
sophisticated HOTs is fully intact in the absence of natural language.
Another sort of evidence relates to the capacities of aphasics, who have
lost their ability to use or comprehend language. Such people are generally
quite adept socially, suggesting that their mind-reading abilities remain
intact. And this has now been conWrmed experimentally in a series of tests
conducted with an a-grammatical aphasic man. Varley (1998) reports
conducting a series of ‘theory-of-mind’ tests (which test for explicit grasp
of the notions of belief and false belief) with an a-grammatic aphasic. This
person had severe diYculties in both producing and comprehending any-
thing resembling a sentence (particularly involving verbs). So it seems very
unlikely that he would have been capable of entertaining a natural lan-
guage sentence of the form, ‘A believes that P’. Yet he passed almost all of
the tests undertaken (which were outlined to him by a combination of
pantomime and single-word explanation).
It seems, then, that a capacity for higher-order thoughts (HOTs) can be
retained in the absence of language. But we also have the tracking-
argument for the conclusion that a capacity for HOTs requires structured,
discrete, representations. So we have the conclusion that higher-order
thought, realistically construed, is independent of language, even in the
case of human beings. And so there is reason to prefer a dispositionalist
HOT-theory over Dennett’s dispositionalist higher-order description
(HOD) theory.
270 Consciousness: theWnal frontier?