Roger Wolcott Sperry

Science traditionally takes the reductionist approach, saying that the collective properties of molecules, or the fundamental units of whatever system you're talking about, are enough to account for all of the system's activity. But this standard approach leaves out one very important additional factor, and that's the spacing and timing of activity — its pattern or form. The components of any system are linked up in different ways, and these possible relationships, especially at the higher levels, are not completely covered by the physical laws for the elementary interactions between atoms and molecules. At some point, the higher properties of the whole begin to take over and govern the fate of its constituents.
A simple way to illustrate this idea is to imagine a molecule in an airplane flying from L.A. to New York. The molecule may be jostled somewhat or held in position by its neighbors, but these lower-level actions are trivial compared to its movement as the plane flies across the continent. If you plot the movement of the molecule through time and space, those features governed by the higher properties of the plane as a whole make those controlled at the level of the molecule insignificant by comparison. The higher properties control the lower, not by direct intervention, but by supervention.

The centermost processes of the brain with which consciousness is presumably associated are simply not understood. They are so far beyond our comprehension that no one I know of has been able to imagine their nature.

With few exceptions, the bulk of the collected lesion evidence up through the 1950s into the early '60s converged to support the picture of a leading, more highly evolved and intellectual left hemisphere and a relatively retarded right hemisphere that by contrast, in the typical righthander brain, is not only mute and agraphic but also dyslexic, word-deaf and apraxic, and lacking generally in higher cognitive function.

The new way of thinking, spawned by the cognitive revolution, shows strong promise ... Reversing previous doctrine in science, the new paradigm affirms that the world we live in is driven not solely by mindless physical forces but, more crucially, by subjective human values. Human values become the underlying key to world change.

I have never been entirely satisfied with the materialistic or behavioristic thesis that a complete explanation of brain function is possible in purely objective terms with no reference whatever to subjective experience; i.e., that in scientific analysis we can confidently and advantageously disregard the subjective properties of the brain process. I do not mean we should abandon the objective approach or repeat the errors of the earlier introspective era. It is just that I find it difficult to believe that the sensations and other subjective experiences per se serve no function, have no operational value and no place in our working models of the brain.

Cognitive introspective psychology and related cognitive science can no longer be ignored experimentally, or written off as "a science of epiphenomena", nor either as something that must, in principle, reduce eventually to neurophysiology. The events of inner experience, as emergent properties of brain processes, become themselves explanatory causal constructs in their own right, interacting at their own level with their own laws and dynamics. The whole world of inner experience (the world of the humanities) long rejected by 20th century scientific materialism, thus becomes recognized and included within the domain of science.

It seems important that the social value factor be more generally recognized as a powerful causal agent in its own right and something to be dealt with directly as such. No more critical task can be projected for the 1970s than that of seeking for civilized society a new, elevated set of value guidelines more suited to man's expanded numbers and new powers over nature, a frame of reference for value priorities that will act to secure and conserve our world instead of destroying it.

What is needed to break the vicious spiral is a world-wide change in attitudes, values, and social policy. As Einstein put it, "We need a substantially new manner of thinking if mankind is to survive."

One of the more important things to come out of the split-brain work, as an indirect spin-off, is a revised concept of the nature of consciousness and its fundamental relation to brain processing. The key development here is a switch from prior non-causal, parallelist views to a new causal, or "interactionist" interpretation that ascribes to inner experience an integral causal control role in brain function and behavior. In effect, and without resorting to dualist views, the mental forces and properties of the conscious mind are restored to the brain of objective science from which they had long been excluded on materialist-behaviorist principles.

When the brain is whole, the unified consciousness of the left and right hemispheres adds up to more than the individual properties of the separate hemispheres.

Instead of maintaining the traditional separation of science and values, cognitive theory says the two come together in brain function. If we are correct in saying that our conscious mental values not only arise from, but also influence brain processing, then it becomes possible to integrate values with the physical world on a scientific rather than supernatural basis. It's been the traditional role of religion to affirm the primary importance of our higher values in this world by invoking a supreme power. In cognitivism, it is science that affirms the powerful controlling role of higher values, and it is able to do so on grounds that are verifiable — that is, testable against reality as it really is.
On these new terms, science no longer upholds a value-empty existence, in which everything, including the human mind, is driven entirely by strictly physical forces of the most elemental kind. We get a vastly revised answer to the old question "What does science leave to believe in?" that gives us a different image of science and the kind of truth science stands for. This new outlook leads to realistic, this world values that provide a strong moral basis for environmentalism and population controls and for policies that would protect the long-term evolving quality of the biosphere.