Ten years ago, I’d read a book about the modern understanding of human color vision: A Vision of the Brain by Semir Zeki, a prominent neuroscientist. This book also provides a summary of the history of theories of color vision. Recently, I realized this subject provides a good example of why there is no knowledge problem from a philsophical viewpoint, that is, why epistemology isn’t a valid field of study — at least to a follower of the empirical methods of St. Thomas Aquinas.
Think of a bright red object, perhaps a child’s ball. Put it in the direct sunlight of a July day and you see a bright red ball. Move it to the shade and you still see the same ball with the same bright red color, though it’s now reflecting a very different set of light-waves. Helmholtz and one or two other great scientists of the 1800s pointed to this fact and noted it disproves the usual theories of color vision — that we perceive colors directly. As late as the 1960s by my personal experience, perhaps to this year, elementary school children were being taught that three primary colors are mixed to produce all other colors. All those colors, especially the primary ones, were treated as having objective and absolute existence.
The theory of the absolute and objective nature of colors survived despite the inconvenience of not being able to deal with that simple counter-observation that the same object reflects different light-waves under different conditions, yet we usually can see that same object as being the same color. In the middle of the 20th century, Edwin Land, an expert in film-technology and founder of Polaroid Corp., thoroughly disproved the theory by showing that without context, without a chance to consider contrast with surrounding areas, we see no colors where there were films of the brightest of reds or oranges. When we’re able to contrast one region with another, our eyes and brains work to produce a colored vision of the world by some biological equivalents of complex mathematical calculations comparing wavelengths of neighboring regions in the world around us. The resulting brain-states generate that useful and often wonderful illusion of a world of color.
Why would the blind processes of evolution produce such a marvel? Our color vision seems to be adapted to the task of allowing us to recognize the same object, say a ripe apple, under various lighting conditions. There is, thus, an immediate sense in which our color vision does help us discern truth, but the colors mislead us by seeming to present themselves as objective aspects of the world. They’re actually codings of a sort, codings of some very complex aspects of reality which give us useful information as we go about our lives. Those codings are embodied objectively in brain-states but the corresponding colors can’t really be found in the external world.
This entire issue helps us to see the legitimacy of epistemological considerations from a neuroscientific and physiological angle, but leads us to understand why epistemology isn’t legitimate as a philosophical enterprise. In principle, we can know the objective truth which lies behind the color vision our eyes and brains produce. We can see, if only by way of formulas and visual simulations, the true wavelengths of light emitted by that bright red ball under different conditions and can even see the brain-states which are the objective foundation of this subjective vision of a colored world. We can also see DNA unraveling and stars exploding billions of years ago, near the beginning of this expansionary phase of the universe. We can control industrial processes by seeing the ‘true’ colors of hot metals being forged and we can see inside the skull of a child so the surgeon can plot out his strategy for dealing with a life-threatening epilepsy. True knowledge problems involve the acquisition of knowledge in a world which is remarkably transparent to the efforts of hard-thinking and hard-working human beings.
In Ways of Thought in the Modern West, I discussed the views of the historian Carroll Quigley who summarized the fundamental Christian philosophy, methodical realism, in these words:
The truth unfolds in time through a communal process.
It’s not easy to be truthful, especially if you raise the stakes and define ‘truthful’ in an active and not just a passive sense. To be truthful in a fuller sense means that you don’t just sit still and try not to lie, you go out and play an active role in this communal process by which the truth unfolds. We can transcend our perceptual and cognitive limitations in many ways, attaining a more complete and less biased understanding of our world by proper use of our brains and these opposing thumbs which allow us to make some remarkable instruments. Problems of knowledge are particular, practical problems which can, at least in principle, be solved in somewhat final ways rather than being part of the open-ended understanding of created being and the story which God is telling with that created being.