David C. Geary is a cognitive psychologist who came up with a theory of the mind that can be roughly summarised as follows:
“Environmental pressures have resulted in the evolution of brain ‘modules’ specialising in processing certain types of information, such as language or facial features. Information is processed by the modules rapidly, automatically and implicitly, resulting in heuristics (rules of thumb) characteristic of the ‘folk’ psychology, biology and physics that form the default patterns for the way we think. But we are also capable of flexible thought that overrides those default patterns. The flexibility is due to the highly plastic frontal areas of our brain responsible for intelligence. Geary refers to the thinking using the evolved modules as biologically primary, and that involving the plastic frontal areas as biologically secondary.” (See here for source.)
In a highly influential paper, Sweller explored Geary’s ideas in a pedagogical context and current thinking around primary and secondary knowledge, stemming largely from his paper, seems to be the following:
Primary knowledge/skill need not be taught explicitly but secondary knowledge/skill must be taught explicitly and usually in a definite context rather than in a generic kind of way.
Although Geary’s ideas are plausible and at least partly ‘true’, they do seem to me to be simplistic.
For example, the vast majority of human beings can speak but many cannot communicate effectively and some do it very badly indeed. Likewise, most human beings have a reasonable level of hand-eye coordination (survival would have depended on it) but some are naturally brilliant and excel at sport while some are clumsy and require huge amounts of practice to even become average. Some people have extraordinary spatial skills and seem to have a sixth sense when it comes to 3D geometry; others are like me and will never be able to reverse park into a tight spot. Some people are born with an ability for abstract reasoning (does that make it primary?) while many, if not most, are not, and have to be trained to do so. Some are born with an innate ability to draw and paint (does that make drawing primary?) while others need intensive training just to draw simple cartoons. Although humans have evolved (you’d expect) to cooperate, , many groups and teams perform very badly.
So for me, the problem with Geary’s ideas is that they ignore the diversity of the human population. What’s primary for some might well be secondary for others. Things are much fuzzier than Geary suggests.