This is a book about how we see: the environment around us (its surfaces, their layout, and their colors and textures); where we are in the environment; whether or not we are moving and, if we are, where we are going; what things are good for; how to do things (to thread a needle or drive an automobile); or why things look as they do.The basic assumption is that vision depends on the eye which is connected to the brain. The (...) author suggests that natural vision depends on the eyes in the head on a body supported by the ground, the brain being only the central organ of a complete visual system. When no constraints are put on the visual system, people look around, walk up to something interesting and move around it so as to see it from all sides, and go from one vista to another. That is natural vision—and what this book is about. (shrink)

For largely historical reasons, information and communication technology in education has been heavily influenced by a form of constructivism based on the transmission and transformation of information. This approach has implications for both learning and teaching in the field. The assumptions underlying the approach are explored and a critique offered. Although the transmission approach is entrenched in procedures and pedagogies, it is increasingly challenged by an action-theoretical form of constructivism. In this 'ecology of ideas', the value of the two theoretical (...) stances might be judged in terms of their practical utility and the contributions they make to understanding ICT. (shrink)