The evolution of humans required performing increasingly hierarchically complex tasks within multiple domains. Hierarchical complexity increases task by task. Tasks occur within, and differ by, determinable domains, their stages of performance measurable using the Model of Hierarchical Complexity. How well one performs within single and multiple domains is considered to indicate intelligence. Original task-initiation is more difficult than imitational learning and can create new domains. Levels of support reduce task difficulty, increasing performance. Task-performance may be generalized to other domains. Stages (...) of developing tools and empathy are presented to demonstrate domains' roles in the evolution of human intelligence. (shrink)

The Model of Hierarchical Complexity is introduced in terms of its main concepts, background, and applications. As a general, quantitative behavioral developmental theory, the Model enables examination of universal patterns of evolution and development. Behavioral tasks are definable and their organization of information in increasingly greater hierarchical, or vertical, complexity is measurable. Fifteen orders of hierarchical complexity account for task performances across domains, ranging from those of machines to creative geniuses. The four most complex orders are demonstrated by postformal stages (...) of thought, which measure beyond formal operations, the highest stage found by Piaget for adults. (shrink)