a given individual has cheated); or it may be able to operate upon infor-
mation called up from long-term memory (as when I recall and try to
explain, for example, what someone may have done the last time we met).
So in virtue of their centrality, central modules will not be so infor-
mationally isolated as peripheral input modules. But the important thing is
that the way in which a module operates on this information should not be
subject to inXuence from the rest of cognition. In any case, we at least need
to enrich the Fodorian account of modularity by distinguishinginfor-
mationalencapsulation fromprocessingencapsulation – whether infor-
mation from elsewhere in cognition canentera modular processor is a
diVerent matter from whether theprocessingwhich the module does can be
inXuenced by other parts of the system.
5.2 Is central cognition unencapsulated?We must now engage with Fodor’s contention that central cognitive
systems are capable of a kind of processing which is unencapsulated, and
that they are therefore unlikely to be modular. A processing system, or
module, is encapsulated if it processes its inputs in a way which is indepen-
dent of the background beliefs of the subject. Perhaps everyone will be
inclined to agree that central processes, such as conscious thought and
decision-making, are not encapsulated in quite this way. But this should
not lead us to conclude thatallcentral processes are unencapsulated, of
course. There might well be a whole host of central modules which perform
their computations non-consciously.
One of the points which Fodor makes is that in decision-making the
products of cognitive processing need to interact with utilities – that is,
with what a person wants and wants to avoid. By contrast, Fodor insists
that one of the functions of the encapsulated and mandatory operation of
the input modules is to prevent them from being prone to what one might
call ‘wishful perceiving’. Selective pressures can presumably be relied upon
to ensure that early stages of input processing are suYciently unprejudiced
not to be inXuenced by the pleasant or unpleasant character of distal
sources of sensory stimulation. We can concede this, and also acknowledge
the obvious point that desires and aversions must play a role in decision
making. But this does nothing to show that a central process of decision
making could not be modular. What it does show is only what one would
want to maintain anyway, that the inputs to central processes are diVerent
from the inputs to perceptual input systems. That is no surprise. So far
nothing counts against the idea of some sort of practical reasoning mod-
ule, which takes as its inputs both current beliefs and current desires, and
operates in such a way as to formulate as its output intentions to act.
Input systems versus central systems 69