National Bestseller / The Art of Possibility

    A frog does not "see" its mother's face, it cannot appreciate a sunset, nor even the nuances of color. It "sees" only what it needs to see in order to eat and to avoid being eaten: small tasty bugs, or the sudden movement of a stork coming in its direction. The frog's eye delivers extremely selective information to the frog's brain. The frog perceives only that which fits into its hardwired categories of perception.

    Human eyes are selective, too, though magnitudes more complex than those of the frog. We think we can see "everything," until we remember that bees make out patterns written in ultraviolet light on flowers, and owls see in the dark. The senses of every species are fine-tuned to perceive information critical to their survival dogs hear sounds above our range of hearing, insects pick up molecular traces emitted from potential mates acres away.

    We perceive only the sensations we are programmed to receive, and our awareness is further restricted by the fact that we recognize only those for which we have mental maps or categories.

    The British neuropsychologist Richard Gregory wrote, "The senses do not give us a picture of the world directly; rather they provide evidence for the checking of hypotheses about what lies before us." And neurophysiologist Donald O. Hebb says, "The `real world' is a construct, and some of the peculiarities of scientific thought become more intelligible when this fact is recognized ... Einstein himself in 1926 told Heisenberg it was nonsense to found a theory on observable facts alone: `In reality the very opposite happens. It is theory which decides what we can observe.'"

    We see a map of the world, not the world itself. But what kind of map is the brain inclined to draw? The answer comes from one of the dictates of evolution, the survival of the fittest. Fundamentally, it is a map that has to do with our very survival; it evolved to provide, as a first priority, information on immediate dangers to life and limb, the ability to distinguish friends and foes, the wherewithal to find food and resources and opportunities for procrea