with their diVerent domains of activity – a mind-reading module for social
relationships and behavioural explanation and prediction; a cheater-detec-
tion module for mediating co-operative exchange; a natural history mod-
ule for processing information about the lifestyles of plants and animals;
and a physics module, crucially implicated in the manufacture of stone
tools. When a language module was added to this set it would, very
naturally, have evolved to take as input the outputs of the various central
modules, so that hominids could talk about social relationships, co-oper-
ative exchange, the biological world, and the world of physical objects and
artefacts. (We think it unlikely that language would have evolvedonlyfor
talking about social relationships, as Mithen, 1996, suggests, following
Dunbar 1996. For given that mind-reading would already have had access
to non-social contents – as it would have to if it was to predict and explain
non-social behaviour – there would then have been a powerful motive to
communicate such contents. See Gomez, 1998.) It also seems plausible that
each of those modules might have altered in such a way as to take linguistic
as well as perceptualinputs, so that merely being told about some event
would be suYcient to invoke the appropriate specialist processing system.
With central modules then taking linguistic inputs and generating lin-
guistic outputs, the stage was set for language to become the intra-cranial
medium of communication between modular systems, hence breaking
down the barriers between specialist areas of cognition in the way Mithen
characterises as distinctive of the modern human mind. All that was
required was for humans to begin exercising their imaginations on a
regular basis, generating sentences internally, in ‘inner speech’, which
could then be taken as input by the various central modular systems. This
process might then have become semi-automatic (either through over-
learning, or through the evolution of further neural connections), so that
even without conscious thought, sentences of LF were constantly gener-
ated to serve as the intermediary between central cognitive systems.
4 Conclusion
In this chapter we have considered how propositional thought-contents
are represented in the human mind/brain. We have argued that some
version of the hypothesis of a ‘language of thought’, as against any strong
form of connectionism, is the most likely. This language may be an innate
and universal ‘Mentalese’, as Fodor has long argued (1975). Or it may, at
least in part, be sentences of natural language which are the vehicles of our
(conscious and/or explicit) thoughts. If this latter possibility proves to be
the case, as we suspect it will, then we have yet another vindication of our
folk-psychological self-image. For it certainlyseemsto us that we entertain
The place of natural language in thought 225