Before revision: This means that not only can an agent directly perceive that there is a horizontal surface or that a tree is a tree, but that a horizontal surface is “walk-on-able” or that a tree is “climb-up-able.” In fact, the agent's perceptual system is so in attuned to the invariant information, Gibson argues, that the agent need not consult any of its prior experiences in order to interact with the environment.
After revision: This means that not only can an agent directly perceive that there is a horizontal surface or that a tree is a tree, but that a horizontal surface is “walk-on-able” or that a tree is “climb-up-able.” In fact, the agent's perceptual system is so attuned to the invariant information, Gibson argues, that the agent need not consult any of its prior experiences in order to interact with the environment.