The Evolution
4
Methodological Outlook
The information that humans must perceive, store, and retrieve
does not occur randomly. Instead it is patterned, and it is these
patterns that offer memory the opportunity to make "sense" of the
world. As a concrete example, consider the two dimensional picture
that the external world imprints on the retina. Taken as raw data
it is no more than a collection of textures, lines, and areas of
shading; but add to this two dimensional picture a set of assumptions
about how the world is constructed (e.g. Waltz, 1975; Horn, 1975) and
that two dimensional picture can with reasonable accuracy and con-
sistency be transformed into a three dimensional view of the world,
replete with the objects, edges, shadows, and cracks that constitute
perceptual understanding.
Strictly speaking, deducing what these assumptions are is not
psychology—it is the study of those properties and constraints
existing in the physical world that are available for exploitation by
a perceptual machine. But since the human mind is a perceptual machine
designed by evolution, such research must inevitably be relevant to
the study of perception.
This paper will take the method of Waltz and Horn one step further,
by applying it to the evolution of cognitive organization in general.
If, as their evidence suggests, the environment has shaped perception,
then why not cognitive organization and memory as well? If human memory