Mind, Body, World- Foundations of Cognitive Science, 2013a

correspondence problem by matching descriptions. However, this also leads a classical
model directly into what is known as the frame problem (Ford & Pylyshyn, 1996;
Pylyshyn, 1987). The frame problem faces any system that has to update classical
descriptions of a changing world. This is because as a property changes, a classical
system must engage in a series of deductions to determine the implications of the
change. The number of possible deductions is astronomical, resulting in the computational
intractability of a purely descriptive system.
The referential links provide a solution to the frame problem. This is because
the tracking of a FINSTed object and the perseverance of the object file for that
object occur without the need of constantly updating the object’s description. The
link between the FINST and the world is established via the causal link from the
world through the proximal stimulus to the operation of early vision. The existence
of the referential link permits the contents of the object file to be refreshed or
updated—not constantly, but only when needed. “One of the purposes of a tag was
to allow the visual system to revisit the tagged object to encode some new property”
(Pylyshyn, 2003b, p. 208).
The notion of revisiting an indexed object in order to update the contents of
an object file when needed, combined with the assumption that visual processing is
embodied in such a way to be of limited order, link Pylyshyn’s (2003b, 2007) theory
of visual cognition to a different theory that is central to embodied cognitive science,
enactive perception (Noë, 2004). Enactive perception realizes that the detailed phenomenal
experience of vision is an illusion because only a small amount of visual
information is ever available to us (Noë, 2002). Enactive perception instead views
perception as a sensorimotor skill that can access information in the world when it
is needed. Rather than building detailed internal models of the world, enactive perception
views the world as its own representation (Noë, 2009); we don’t encode an
internal model of the world, we inspect the outer world when required or desired.
This account of enactive perception mirrors the role of referential links to the distal
world in Pylyshyn’s theory of visual cognition.
Of course, enactive perception assumes much more than information in the
world is accessed, and not encoded. It also assumes that the goal of perception is to
guide bodily actions upon the world. “Perceiving is a way of acting. Perception is not
something that happens to us, or in us. It is something we do” (Noë, 2004, p. 1). This
view of perception arises because enactive perception is largely inspired by Gibson’s
(1966, 1979) ecological approach to perception. Actions on the world were central to
Gibson. He proposed that perceiving agents “picked up” the affordances of objects
in the world, where an affordance is a possible action that an agent could perform
on or with an object.
Actions on the world (ANCHORs) provide a further link between Pylyshyn’s
(2003b, 2007) theory of visual cognition and enactive perception, and consequently
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