Summary of Presentation by Prof. Murray on Piaget and Cognitive Development

Summary prepared by Robert Armengol and David Jakhelln (additions and comments by Frawley)

Piaget's Theory

[summary based on Prof. Murray's lecture and his paper in the Wiley Encyclopedia of Psychology (New York: John Wiley and Sons, 1984)]

Piaget helped to found the school of thought known as genetic epistemology. Genetic epistemology asks the following questions:

What is knowledge?

From whence does it come?

What are the conditions that make it possible?

Prof. Murray observes: "Piaget's solution is 'constructivism,' a position which holds that the fundamental categories and structures of our minds are not given a priori, but are constructed by us in the course of development through evolving systems by which we act on and transform the environment and our own minds. The succeeding levels or stages are always reformulations of reconstructions of the preceding way of acting on the world and validating knowledge and are always more consistent and more coherent than the preceding way."

NOTE: this means that Piaget is aligned with those who hold that development is discontinuous -- or that developmental stages are radical redoings of earlier stages. This contrasts with those who hold that development is continuous, or that the initial state has all the power it needs to devlop at later states and that development is a quantitative enhancement of earlier states rather than a qualitative change.
Piaget's theory is a competence theory. This means that if an ideal person possessed the structures and mechanisms that Piaget postulates, then the person could develop thought and logic.
Problem: the measurment in Piaget's experiments, and most of the criticisms of his proposals, is performance. Cf. Baillargeon's objections.
The basic ingredients of the theory are structures and functions.


The structure is knowledge. Through innate reflexes, actions and transformations become more differentiated and integrated. The structure of action develops, and it runs from primitive reflexes to logic, mathematics, and scientific thought. The pivotal point in the development of logical thought and rationality comes when the system of actions of infancy and early childhood become interiorized and reversible.


Assimilation - Structures tend to preserve or conserve themselves. This promotes integration and similarity between the elements or content of the structure.

Accommodation - A mechanism by which cognitive structure is modified or reconstructed to enable it to assimilate or incorporate new information or content.

Equilibration - the balancing of the two above functional invariants. Disequilibrium provides the potential for cognitive advancement.

The process is guided by reflective abstraction - structures at one level are reflected up to a higher level and become the content of the more general structures of the new system. Piaget proposed that individuals go through stages of intellectual development:

1. Sensorimotor 0-2 yrs.

2. Preoperational 2-7 yrs.

3. Concrete Operational 7-11 yrs.

4. Formal Operational 11-12 yrs.

Each stage moves the individual away from an egocentric view of the world. Also the stages result in the individual's ability to reason noncontextually.

* * *

Prof. Murray's Lecture
Prof. Murray supported Piaget's theory with evidence for stages in cognitive development. Murray defined a stage as any revolutionary change in cognitive behavior that manifests itself in our need to restructure scientific explanations which previously held true. He argued that development can be thought of as discontinuous, that is, stage-like, if it requires successive and major qualitative changes or reanalyses of the observed behavior.

What is a stage? How do you know an individual is in one? What causes stages? To claim that there is a stage, you have the responsibility of stating the characteristics that define the stage and placement therein. For example, Piagetians claim that knowledge of number precedes knowledge of mass (7-8), which precedes knowledge of weight (8-9), which precedes knowledge of volume (10-11). These stages are seen as striking developmental changes tied to these maturational times.
We focused around one type of experiment that studies the differing abilities of adults and children to learn and relearn particular relationships. In the simple test we discussed, subjects are required to "learn," though positive reinforcement, that two large square figures of two different colors are "correct," whereas two small square figures of the same colors are "incorrect." Once subjects have satisfactorily acquired the knowledge, they are required to interpret different matching models with the same figures. In one instance, they must conduct a complete "reversal shift" in which the small figures become "correct" and the large ones "incorrect." In another instance, they must conduct a "non-reversal" shift by learning that the objects of a particular color are "correct" regardless of size while the other two objects are "incorrect."

The study shows that while adults conduct reversal shifts more easily, children are inclined to do better on non-reversal shifts. We considered several explanations for the differing behavior. Our predominant hypothesis centered around the idea that adults have already undergone a stage-like cognitive change in which a mental mechanism has developed that allows the subject to immediately assume size as a factor of correctness; such a mechanism favors the reversal shift, in which size interpretation is still the deciding computation. Young children, however, may be in an earlier stage in which each object is treated as a "unit" of correctness or incorrectness; in such a case the non-reversal shift is easier because it requires the overall change in correctness of only two stimuli, rather than all four.

Murray concluded his lecture by outlining four theories of what needs to be "pre-wired" in humans in order for development to occur.

Or, as he said: "What do you need to put in a child for him/her to end up like you later?"

The theories, which follow, span the spectrum from continuity to discontinuity:

1. The mind/brain is an information processing machine with storage capability and an algorithmic computability that is static throughout life.

2. At the onset of life, we are unconsciously motivated and develop cognitive principles based on pleasure and interpretation of reality.

3. We are born with cognitive reflexes and act initially on conditionality. We learn though imitation and refinement of our reactions.

4. We are born with reflexes that allow an equilibration of assimilation and acommodation to occur through maturation, learning, and social interaction.