Samenvatting
A general theory of locomotor behaviour in relation to physical objects is presented. Since the controlling stimulation for such behaviour is mainly optical, this involves novel assumptions about object perception and about what is called "visual kinaesthesis". Evidence for these assumptions cited. On the basis of this theory it is possible to suppose that animals are visually oriented to the surfaces of their environment, not merely to light as such. In short, it is possible to explain why they seem to have space perception. Implications of this approach for mazelearning are pointed out.