This Monograph presents a theory of cognitive development. The theory argues that the mind develops across three fronts. The first refers to a general processing system that defines the general potentials of mind to develop cognitive strategies and skills. The second refers to a hypercognitive system that governs self-understanding and self-regulation. The third involves a set of specialized structural systems (SSSs) that are responsible for the representation and processing of different reality domains. There are specific forces that are responsible for this organization of mind. These are expressed in the Monograph in terms of a set of five organizational principles. The developmental course of the major systems is outlined. Developmental change is ascribed by the theory to the interaction between the various systems. Different types of development require different change mechanisms. Five studies are presented that provide empirical support for these postulates. Study 1 demonstrated the organizational power of principles and SSSs. Study 2 showed that the SSSs constrain the effect of learning. Study 3 established that the hypercognitive system does function as the interface between tasks and SSS-specific processes or between SSSs and general cognitive functions such as attention and memory. Study 4 investigated the relations between one of the components of the processing system, storage, and two different SSSs expressed via two different symbolic systems, namely, the numeric and the imaginal. Finally, Study 5 examined the interaction between the components of the processing system and the relations between each of these components and one SSS, namely, the quantitative-relational SSS. The theoretical implications of these studies with regard to general issues, such as the nature of representation, the causation of cognitive change, and individual differences in cognitive development, are discussed in the concluding chapter.

This essay first summarizes an overarching theory of cognitive organization and development. This theory claims that the human mind involves (1) several specialized structural systems dealing with different domains of relations in the environment, (2) a central representational capacity system, (3) general inferential processes, and (4) consciousness. These systems interact dynamically during development so that changes in each are related to changes in others. The changes in all systems and the change mechanisms are described. This theory integrates research and theorizing from cognitive, developmental, and differential psychology. Based on this theory, a model for education is proposed that specifies, first, educational priorities for different phases of development according to the cognitive developmental milestones associated with each phase. The theory also specifies how education can educate students to (1) construct mental models for the sake of conceptual change, (2) use their central representational capacity efficiently, (3) advance analogical and deductive reasoning, (4) learn how to learn, and (5) become critical and creative thinkers. The theory is offered as an overarching paradigm for the architecture, the development, and the education of the human mind.