Our four-footed companions go through life on a quite different timescale from we humans. Matilda Beagle was the second dog that we have nursed through old-age infirmities and held as she left this world, this one shortly after her 13th birthday. As I come through the human equivalent of aging myself, this passing could not help but prompt a lot of self-reflection on the nature of life and the absence of it.
During the last three years, as I have blogged frequently about the nature of human perception and volition/choice/free-will, I have tested my evolving understandings against a furry friend who lived with her nose to the ground much of the time. How was her perception of the world different from, or similar to, mine?
Naive realism and the Cartesian theater
This post flirts with two concepts in philosophy and neuroscience. The first is called naive realism, which is the debate over whether we “see” an objective reality in the world, or rather if it is merely a limited and subjective construction by our brain from limited sensory perception. As a related idea, philosopher and neuroscientist Daniel Dennett coined the term “Cartesian theater” to describe the inaccurate perception that a “little me” inside my brain is “watching” a kind of screen that displays the outside world with fidelity.  To Dennett, consciousness is a much more like a continuous brain construction of “multiple drafts” of reality from lots of imperfect information sources.
I am not going deeply into either of these debates. It is easy to demonstrate that my human sensory perceptions are less than accurate, and we can ponder forever how deep that inaccuracy goes. However, you and I live most of the time assuming that this “Cartesian theater” is “real life.” We probably could not make it through the day without that assumption, or illusion, if you will. Asking “What is real?” is maybe too Zen for this post.
When I pondered how Matilda Beagle “saw” the world, it became obvious to me that my own senses are limited far more than I had previously considered. Especially in her later years, Matilda’s eyesight was not very good. More than once we would walk within six feet of a rabbit frozen in the grass, waiting for us to pass by, or perhaps preparing to “make a run for it.” Matilda would invariably ignore the rabbit, and instead quickly bolt, in a very anti-Wayne-Gretsky style,  to where the rabbit had just been, stick her nose in the ground there, and begin to sniff her way toward the rabbit, who had by now darted to safety. She was more tracker than attacker.
Many scientific accounts estimate that a beagle has 220 million or more scent receptors, compared with a mere five million in humans. The beagle nose is also constructed differently from humans, such that it can breathe in and out while it simultaneously “holds” an odor for evaluation. This is a difficult concept to wrap our minds around, but beagles likely “see the world” primarily as a multidimensional map of where numerous identifiable odors are relative to each other, and adding in their memory of past smells. Despite attempts at obedience school, “Heel,” was not in her vocabulary; she followed her nose everywhere. Matilda never just went for a “normal” walk.
Whenever we would stay in a new place such as a hotel, I liked to test Matilda after leaving our room for the evening’s relief time by letting her lead me back to the correct room. She never failed, nose to the ground the entire time. What was she smelling that I could not? And how did this map “look” to her in her own “Cartesian theater.”
Not only is the sense of human smell limited in our human “naive realism” view of the world around us, but our vision is not that great either. We see color only in a limited spectrum of light, while some other animals (although not dogs) can “see” ultraviolet or infrared colors. Most of us have three types of functioning “cones” in our retinas, processing light frequencies that we call red, blue and green. Our peripheral vision uses no cones at all, however our brains “construct” a picture for us that seems to be a continuous spectrum of color in a 180-degree field of vision.
Dogs have only blue and yellow cones, and so Matilda’s color spectrum would appear to be quite different from ours. Mantis shrimp, on the other hand, appear to have twelve “channels” of color perception, although their brain biology is quite different from that of humans. Add to human visual limitation the complexities of our retinal “blind spot,” our unperceived (to us) rapid eye movements called “saccades,” and our incessant (and usually unperceived) blinking eyelids. It quickly becomes clear that the smooth-moving, detailed picture of the world that I perceive as being fed from my eyes is more of a brain-constructed animation than I prefer to consider.
Dennett describes the main function of the brain as an “expectations generator,” and as it such we most often “see” only things that we expect to see. If you think you are “seeing everything,” the classic and short 1999 visual perception test by psychologists Daniel Simons and Christopher Chabris may put that to rest. If you have not seen it, this video is worth a view:
Some more complexity: I have written before about how our brains use a form of logarithmic calculation to compress both a large light frequency spectrum and widely-varying light intensities into the brain perception of a linear scale, such as in a rainbow. This compresses information that would otherwise take a large amount of “brain bits” to be stored into a much smaller package.
And then there is hearing. Matilda had me beat there as well for most of her life. Hearing is also a sensory effect where a broad range of perceptible frequencies and intensities are compressed into logarithm-like smaller packages we interpret as apparently-linear “musical scales.” Matilda would frequently rouse from a dead sleep, snap her head high, and look for the source of a sound that eluded my hearing. She did not care for music, however (or at least my guitar playing). I had long thought that the beagle’s long floppy ears aided their hearing, but it appears to more be related to focusing odors from the ground. The nose again.
That is just a partial stab at what Matilda “saw” different from me in this world. A “reality” with a different color spectrum, but intensified smells, mapped by location and memory, and a more focused (and too-often selective and obstinate) ear, all adding to her “Cartesian theater.” Whose perceived world was “more real,” hers or mine? And what about her perception of time itself, her thirteen years from skinny pup to chunky old age compared with my three-score and ten similar progression?
You can find numerous videos on YouTube of dogs gleefully recognizing their owners after, say, coming home from extended military service. I have to say here that these are nothing compared with Matilda’s over-the-top reaction after we would come home from an hour’s trip to the grocery store. However, as my own hearing began to fade, so did Matilda’s. She began to doze through most hours of the day and night, even to the point of sleeping though our noisy returns home with bags of groceries. You could watch her still dream of chasing rabbit smells, however, her legs even moving, when she would no longer venture outside the yard. As T.S. Eliot wrote:
In our rhythm of earthly life we tire of light. We are glad
when the day ends, when the play ends; and ecstasy is too
We are children quickly tired: children who are up in the night
and fall asleep as the rocket is fired; and the day is long for
work or play.
Here is singer-songwriter and lefty guitarist Bill Staines singing his composition about “Old Dogs.”
- Dennett, Daniel C. Consciousness Explained. Back Bay Books, Little, Brown, 2007.
- Legendary hockey player Wayne Gretsky famously explained his “secret” to good hockey: “I skate to where the puck is going to be, not where it has been.”
- Kids, can you say epistemology?
- Hearing, seeing, and choosing in logarithms – part 1
- Hearing, seeing, and choosing in logarithms – part 2
For additional posts on probability, volition and ethics, follow the Dice icon back or forward where it appears.
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