ABSTRACT
The nature and structures of human abilities have exercised the minds of psychologists for over a century and of philosophers long before then. In 1904, Spearman outlined his simple, elegant theory of intelligence, known as the two-factor theory. A general ability factor called 'g' was considered as fixed; specific ability factors called V were open to environmental influence. Even today, psychologists can be overheard to describe children in terms of 'g'. The development of the child's thinking follows a series of stages of complexity in the mental operations he can perform. Each is a necessary precondition of the next. Therefore it is of vital importance that the child engages in the sort of experience appropriate to his stage of development. If he lacks this experience, the whole of his subsequent development will suffer. Therefore, the perceptual learning of the child in his early years must be the major concern of the teacher.
