In "seeing" a landscape, one both "chooses" what to see and passively allows nature to act upon one's eyes and subconscious mind. Because of this continuous oscillation between will and passivity, one can never truly comprehend what scientists and painters alike have called the "champ de vision," or "field of vision." In the end, houses are perceived as houses, trees as trees, and roads as roads, and they are not simply colored light acting upon the retina. Certain forms contain powerful meanings and associations for individual viewers, others are blander, and each participates (unequally) in a larger abstraction called "the landscape."