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

Sections 4.5 through 4.7. These sections investigate the kinds of tasks that artificial
neural networks can accomplish and relate them to those that can be accomplished
by the devices that have inspired the classical approach. The general theme of these
sections is that artificial neural networks belong to the class of universal machines.
Sections 4.8 through 4.13 focus on the algorithmic level of investigation of
connectionist theories. Modern artificial neural networks employ several layers of
processing units that create interesting representations which are used to mediate
input-output relationships. At the algorithmic level, one must explore the internal
structure of these representations in an attempt to inform cognitive theory. These
sections illustrate a number of different techniques for this investigation.
Architectural issues are the topics of Sections 4.14 through 4.17. In particular,
these sections show that researchers must seek the simplest possible networks for
solving tasks of interest, and they point out that some interesting cognitive phenomena
can be captured by extremely simple networks.
The chapter ends with an examination of the properties of connectionist cognitive
science, contrasting the various topics introduced in the current chapter with
those that were explored in Chapter 3 on classical cognitive science.
4.1 Nurture versus Nature
The second chapter of John Locke’s (1977) An Essay Concerning Human Understanding,
originally published in 1706, begins as follows:
It is an established opinion among some men that there are in the understanding
certain innate principles; some primary notions, characters, as it were, stamped
upon the mind of man, which the soul receives in its very first being, and brings
into the world with it. (Locke, 1977, p. 17)
Locke’s most famous work was a reaction against this view; of the “some men” being
referred to, the most prominent was Descartes himself (Thilly, 1900).
Locke’s Essay criticized Cartesian philosophy, questioning its fundamental
teachings, its core principles and their necessary implications, and its arguments
for innate ideas, not to mention all scholars who maintained the existence of innate
ideas (Thilly, 1900). Locke’s goal was to replace Cartesian rationalism with empiricism,
the view that the source of ideas was experience. Locke (1977) aimed to show
“how men, barely by the use of their natural faculties, may attain to all of the knowledge
they have without the help of any innate impressions” (p. 17). Locke argued for
experience over innateness, for nurture over nature.
The empiricism of Locke and his descendants provided a viable and popular
alternative to Cartesian philosophy (Aune, 1970). It was also a primary influence on
some of the psychological theories that appeared in the late nineteenth and early
126 Chapter 4