Wednesday, February 29, 2012

Schema Theory and The Copy View

The following is a short pragmatic take on the history of Western philosophy with regard to mind conceived of as a mirror of nature.


The Copy View
The “copy view” is the position that perception, memory, and other functions of mind are matters of finding or making mental models in the form of internal subjective replicas of external objective reality. Cognition then is the process of using these structures to draw conclusions. Knowledge in this view is having mental structures that are accurate reflections of reality. The copy view differs from other hypotheses about mental structures such as scripts, categories, and schemata in that it goes further in not merely asserting the utility of abstract notions of organizational frameworks but also holding that these representational structures have the same sort of structure of the objective reality they represent. In the copy view, the concept “automobile” is a mental version of a physical automobile where attributes of the mental copy can be matched up with attributes of the objective automobile in a one-to-one correspondence.

Platonism
The copy view of mind has roots going back at least to Plato. In the Platonic view we have knowledge if our forms (categories, concepts, schemes) are the ideal forms. We have true knowledge of “automobile” if our mental version of automobile is the ideal automobile.  In the Platonic view, even numbers share in the essence Duality, and a sick person is participating in the essence Fever. A golden retriever we encounter on the street is just a shadow on the wall of Plato’s Cave cast by the ideal essence of Dogness which is more real than any individual dog.

These ideal forms are educed (brought out from within) through proper education rather than induced (imposed from without). The ideal forms are innate. Plato thought that they are already possessed and can be demonstrated to be so by educing them through Socratic questioning.

Today we deride his tendency to treat abstract constructs as concrete entities with independent existence as “reification.” While the notion of ideal forms sounds pretty nutty today, the Platonic view of knowledge lives on to the extent we formulate mind in terms of subjective mental copies of objective phenomena. (And though we don’t generally reify Duality, or Fever, or Dogness, many people still reify some concepts as in the Christian’s maxim “Jesus is the Truth, the Life, and the Way.”)

Rationalism
Both the Rationalists and Empiricists tacitly accepted the copy view but had different ideas about how we generate conclusions from these mental copies.

The Rationalists (such as Descartes) thought that we have an innate faculty called Reason (a Platonic essence) which we can access to make proper conclusions. In fact, he thought we could generate knowledge through thinking alone (as in his deduction and subsequent momentous pronouncement that he exists, e.g. cogito ergo sum).

Empiricism
The empiricists (notably Locke and Hume) denied that there is knowledge independent of experience. They asserted that there is nothing in the mind that was not first in the senses. The is no faculty of Reason (actually, I think for Locke there was, but for the later more thorough-going empiricist Hume, no) or any knowledge whatsoever that is there in the mind until it is gained through interaction with the world. For empiricists, all knowledge comes from experience, and what we experience are our sensory perceptions. We accumulate mental copies and learn associations between them. (Thorndike was in the empiricist tradition as an associationist. Skinner does not seem to take the copy view and did not hypothesize abstract mental structures of any kind for knowledge).

Empiricists and Rationalists are historically in agreement about the premise of mental structures and knowledge as fundamentally representational in nature—the copy view. The disagreements were about whether or not there is non-experiential knowledge and whether reason is an innate faculty.

The Kantian Synthesis
Enter Kant to try to resolve the impasse between Rationalists and Empiricists. Kant thought that the empiricists had made valid criticisms of the rationalist view (such as through Hume’s thought experiment of a baby deprived of all sensations until its 18th year. It seems reasonable to think that this 18 year old would not possess any knowledge whatsoever.) But Kant thought the empiricist’s view was inadequate since there must be some mechanism prior to experience to give structure to perceptions. Otherwise no one could ever identify an object as the same object under different lighting conditions or different angles of view as sensory perceptions are never exactly the same and always in flux. Kant famously summarized, "Concepts without percepts are empty; percepts without concepts are blind."

Unlike the empiricists, Kant didn’t think reality was directly knowable through the senses because our language and senses amount to a sort of lens which intervenes between a mental “eye” and its object. (Such ocular metaphor’s for knowledge--to “see” is to know, beliefs are “views,” memories are reviewed by “the mind’s eye,”  new understanding is “insight”--are typical of the copy view and are deeply embedded in our language.) Because of the filtering properties of the “lens,” we can’t know if our copies are accurate.

Kant agreed with the empiricists that there is nothing in the mind that was not first in the senses but made an exception for what was already in the mind from the very beginning--not any knowledge or any built-in faculty of reason but rather a system that creates structure to our experiences. He struck middle ground by proposing that certain concepts or categories (certain schemes or schemata in our terms) such as for quantity, time, and causality are innate.

Piaget can be thought of as having proven Kant wrong to some degree by showing that the schemes Kant wrote about are actually developed over time rather than in-born.

Note that the schemes or categories for Kant and Piaget are not mental copies of reality but rather more abstract mental structures; however, the copy view persisted for Kantians with regard to true beliefs and accurate memories. Kant left us with the problem of being hopelessly out of touch with reality since in the Kantian picture, our senses always intervene between the mind and what it perceives and our languages impose categories on thought and limits on what thoughts are thinkable.

We don’t have a way to directly compare a belief to reality to see if it properly represents it, since in the Kantian view, reality is only indirectly accessible to mind. Only the representations (categories, schemes) of reality rather than reality itself are directly known.  Note the parallel to the Platonic problem of living in a world of shadows. 

Pragmatism
The pragmatists (Peirce, James, Dewey) got us around the Platonic appearance-reality quandary by questioning whether beliefs are best thought of as representations of reality. With the benefit of the Darwinian perspective, they saw language use and rational thought in general as evolving to cope with reality rather than evolving to represent reality.

There is no evolutionary reason why the structure of thought would need to be fundamentally representational to be useful for helping us get what we want, so it is doubtful that the “copy view” captures anything fundamental about cognition.  

While there may be some mental activity best imagined as a matter of making copies, the accuracy of copying is only of secondary importance to utility. In general, thinking is a sort of tool use, and tools don’t need to copy reality to be useful. The relevant test of a hammer is whether it drives nails, not whether it correctly copies reality. So it is with the human tools we call language and rational thought where the relevant test is the ability to coordinate human behavior to meet our various desires and needs.

Schema Theory and The Copy View
Like copies, schemata are mental structures, but their organization is more abstract. The “automobile” concept is not though of as aimed at a Platonic ideal form but a malleable framework of abstract structures. In the schema view, mind is a structure of structures as well as the on-going processes of structuring and restructuring.

In schema theory, memory is not a matter of re-presenting a stored mental copy to the mind’s eye. Memory retrieval is a process of construction.

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