Self-recognition and its advanced form, introspection, are two of the defining characteristics that we tend to think of as uniquely human. Yet how many of us actually reflect on the miraculous nature in which we have been formed, be it through creation or evolution?
Perhaps the most excellent example of the miraculous nature of the human form is the human visual-perceptual system. When we open our eyes, we are immediately presented with a three-dimensional representation of the world around us.
We open our eyes and we see, and yet this process is not so simple; it’s more complex than we ever imagined. How do we go from light-sensing photoreceptor cells on the retina to a two-dimensional image and from there to a world that has depth, motion and color? How does the visual system “”know”” the boundaries of distinct objects? Why is it that when we see a propeller or a wheel spinning we sometimes see it as spinning in the opposite direction from the direction in which we know it to be moving? Why is it that the leading edge of a moving object is distinct while its motion often blurs the trailing edge?
The answer lies in the various biophysical aspects of the eye, but also more importantly in problem-solving shortcuts or heuristics the brain employs to reduce the computational burden of perception. These computations are so complex that they have befuddled science’s best efforts to replicate the visual system. It is perhaps these researchers who, recognizant of the ineptness of their own efforts, appreciate the human visual system most fully and in a way that should impress upon the rest of us the greatness of this gift that we have been given and often take for granted.
And it is not merely a case of vision against a backdrop of blindness by which we should measure our gratitude, but by an entire gradient of vision. People exist who have deficits that disable certain aspects of their vision.
Cortical achromatopsia results in an inability to see color, relegating the perceptual world to shades of gray. Balint’s syndrome results in an inability to perceive motion, presenting the world as a series of static snapshots instead of as a continuum. Blindsight results in a loss of visual consciousness so that, though the person has the ability to see, they have lost the ability to perceive that which has been seen.
I have tried to emphasize feelings of awe, humility and gratitude in explaining the visual system, not only because it is appropriate, but also because it is important to reflect outside the realm of graded curves and rote memorization of class material. This reflection will allow us to remind ourselves of the relative insignificance of man’s achievements and allow us to regain a more humble and perhaps thoughtful attitude toward the knowledge we acquire and the progress we make.
It is especially important for this to occur here at UCSD because of our position as a research school. Science has often given humanity powerful tools –tools that allow for great benefits, but also great abuses. The most recent and obvious example of this being chemical and biological weaponry, but there have also been more historical abuses. The idea of eugenics — the prohibition of people with genetic “”flaws”” to reproduce in order to “”improve”” the gene pool — resulted from a misapplication of our understanding of human genetic heretability. The unethical, inhumane experiments of Nazi scientists were carried out in the name of science ,and the list is long and unfortunate.
There will be times when the issues will not be as clear, such as stem cell research and genetically modified foods, and at these times approaching them with appropriate humility and reflection as to the consequences of the research is of paramount importance.
The recognition that although we possess the ability to do something, we should not always do it, should remain ubiquitous in the researcher’s mind.
In conclusion, let us use our vision and our intellect, which is ultimately the source of our perception, for the betterment of ourselves as individuals, as a community and as members of humanity, so we may improve the human condition.
“”The lightning all but snatches away their sight; every time the light [helps] them, they walk therein, and when the darkness grows on them, they stand still. And if God willed, He could take away their faculty of hearing and seeing; for God hath power over all things,”” reads the Quran in al-Baqarah 2:20.8.
