What Science Teaches
Perception makes the world go ’round. At least this is how we perceive it. Truly, we do not know what the real world might be. We can only see it through our sense-making capacities, which include our physical senses, scientific equipment, and experiments. None of these gives us the ability to know what might be going on outside of our very limited perceptual means. Yet as humans, perceptions are all we have to answer our biggest questions: What is life’s meaning? What is the Universe? Who are we as a species? The ultimate question for Western science was first asked in the early 1700s by Leibniz: “Why is there something rather than nothing?”
Even with our very limited means, understanding how we perceive has become a critical element in theories of biology, psychology, epistemology, and cosmology. If we understand both the capacities and limitations of our perceptual abilities, we might be able to learn how life came to be, how it works. And we might develop physics that can better explain the workings of the cosmos. We might even understand ourselves better and stop driving one another crazy.
Perception in Biology
Living systems are learning systems. They form and survive only as they stay actively engaged in exchanging information with their environment. Without cognition or sense making, there can be no life. In the 1970s, Humberto Maturana and Francisco Varela made a brilliant contribution to our understanding of the role of cognition in all life. “The Santiago Theory of Cognition” (they were researchers in Chile) illuminates the role of perception in living systems—plants, animals, humans.1 The study of how living systems know and learn is now a specialized, interdisciplinary field: cognitive science.
Cognition is not a representation of an independently existing world. It is a continuous process of bringing forth a world through the process of living. We cannot see the world as a self-existing independent object—it can only be perceived through the physical senses of every species. Perception varies by species—bats use sound, dogs use hearing and smell, bees use light waves—yet the process of perception is identical. The living being chooses what to notice and then decides how it will respond to what it just chose to pay attention to. This is the essential freedom of all living beings.
As Maturana and Varela note: “You can disturb a living system; you can never direct it.” You can’t boss life around unless you force it to become lifeless.
As a living system decides what to notice from the unlimited stimuli in its environment, it shapes the environment into its own little world. “It brings forth a world,”2 through what it chooses to notice. It doesn’t matter what exists beyond the perceptual filters of the organism. By its choices, it determines what’s relevant and what’s not. Everything else disappears.
The freedom to decide what to notice and how to respond has a fundamental impact on the environment. It changes it. The environment that the organism creates becomes its means of support for continuing to live. Or not. If it shapes it, as we humans have done, in narrow, life-destroying ways, eventually the environment fails and so too does the species.
Perception in Physics
The thought experiment known as Schrödinger’s Cat was designed by Erwin Schrödinger to put an end to the “central mystery” of quantum physics.3 His experiment was meant to refute the double-slit experiment in which the behavior of electrons, either as waves or particles, depended on the experiment and the expectations of a human observer. The electrons changed their behavior according to what the observer was looking for.
In his thought experiment, the cat was in a closed box and its fate was determined by the observer. Even though Schrödinger had expected to disprove such an absurdity, this experiment only substantiated this fundamental weirdness. Years later, Schrödinger opined, “I wish I’d never met the cat.”
The first evidence that perception made a difference in observed behaviors of light appeared more than 300 years ago, in the 1790s in the work of Thomas Young. Experimentation continued and, up until 1925, there was no satisfactory theory of quantum mechanics. And then, by the end of 1926, there were two, each different from the other.4 Since then, the double-slit experiment has continued to perplex, disturb, depress, and stimulate quantum theorists. They can calculate using very different theories and each still get useful results. The Nobel Prize for Physics was awarded first to a father, then later to his son, for their research that gave opposite explanations, both of which were right.5
Very recently (2013), researchers in Japan and Italy announced the results of what is the definitive double-slit experiment, where they observed the behavior of single electrons. Using a membrane with slits that were each 62 nanometers wide (a nanometer is a billionth of a meter), they observed the behavior of electrons as they passed through the slits when both were open or when only one was open. The patterns made it clear that the electrons were acting as both waves and particles, the same as in past experiments. “Each electron seemed to ‘know’ not only what the exact experimental set-up was at the time it flew through the slit, but also what had happened to the electrons that went before it and the ones that would come after it.”6
Richard Feynman, the preeminent American physicist, said that the double-slit experiment contains “the central mystery, indeed the only mystery” of quantum mechanics. It has remained so to this day. It might be demonstrating a different role for perception; it might be demonstrating the limits of physics as currently understood; it might be pointing to the deeper mystery of how all is interconnected.
And nobody knows how the world can be like that.7
I think I can safely say that nobody understands quantum mechanics. . . .
Do not keep saying to yourself, if you can possibly avoid it, “But how can it be like that?”
Nobody knows how it can be like that.
Richard Feynman, physicist