The human young must learn to perceive these affordances, in some degree at least, but the young of some animals do not have time to learn the ones that are crucial for survival.

(1979). Perceiving Acting and Knowing: Toward an Ecological Psychology. ).

In his classic work The Perception of the Visual World (1950) he rejected the then fashionable theory of behaviorism for a view based on his own experimental work which pioneered the idea that animals 'sampled' information from the 'ambient' outside world. They are all prosperous.