Here, Hofstadter returns to the puzzle that has focussed his life: What is consciousness? He now asks it as, What is a person? Here’s how I interpret his exploration of this puzzle.
The title supplies the short answer: A person is a strange loop. To explain that concept, he starts with feedback, first as an unwanted side effect of outputs looping back as inputs, as when a microphone screeches in the middle of the gym. He escalates that to the feedback loop we experience in a hall of mirrors, or when a video camera videos its own output on a screen. More complex is the feedback loop we use when we control home heating with a thermostat.
More complex still are the biological feedback loops that maintain bodily function. These loops intersect in many ways; they form a feedback web. To describe life is to describe feedback loops and webs.
But there’s more: animal life includes feedback loops within the nervous system. We focus on something we see because we want more data. The visual centre has sent its outputs to other parts of the brain which in turn send their outputs to still other parts, and one of those parts triggers the “turn your head and look more closely” action.
In short, we are perception machines. All living things perceive their environment in the sense that they respond to those features of it that their sensors monitor. That environment includes their own internal states. These are the feedback loops that enable living things to maintain their life processes over time.
Humans, and many other animals, not only perceive their environment, they perceive their bodies in space, and that perception becomes part of the feedback web that results in actions. Some animals perceive at another level: they perceive themselves. They know that they are not the chair that they are sitting on, nor the human who is sitting on the chair. But this self-awareness is limited: a cat does not know that what it sees in the mirror is itself, not another cat.
Finally, some animals are able to perceive themselves perceiving themselves. This is the strange loop of Hofstadter’s title. The famous mirror test demonstrating that chimpanzees have a self-image shows what he means. Humans have an even more complex capability: we perceive ourselves perceiving ourselves perceiving ourselves. This recursion constitutes what Hofstadter thinks of as a person. In fact, there seems to be only a practical limit to how far this recursion can go. Our brains are huge and complex, but there is a limit to the amount of information included in any one moment of awareness. At the conscious level, the recursion is expressed in symbols, primarily via language, but also via all the other mediums we use to articulate our awareness and understanding of ourselves, each other, and the world around us.
That’s Hofstadter’s thesis as briefly as I can explain it. To me, it’s the most compelling account of consciousness, of a person, that I’ve read. It has the virtue of being testable. Hofstadter himself supplies the basic test. He reminds us of animal behaviours that suggest awareness, and more importantly, of the observation that a human grows in awareness of its surroundings, its body, and of its self. Babies are born barely able to respond to external stimuli. By around 5 or 6 years of age, a human has a well-developed self: “I” means not only the body, it includes desires and impulses, abilities and skills, the recognition of the things in its environment, memories of yesterday and the day before, and expectations of the future.
Most characteristically, the self is the way those awarenesses are expressed, translated into stories, songs, pictures, and so on. The child is a person because it knows itself, it has constructed a narrative of itself as an agent in the past, present, and future. And as dementia destroys the brain, it also destroys the person. The narrative that constitutes the self diminishes bit by bit, and we observe the terrifying reality that a body can be empty, a shell with no self inhabiting it.
The extension of the self into time and space, into memories and ideas, into symbolic representations, is uniquely human. To paraphrase Hofstadter, a dog will remember that a table scrap is delicious and therefore worth begging for, but it doesn’t reminisce with other dogs about The Best Table Scraps I Ever Ate.
Hofstadter includes a couple of chapters on how Goedel’s theorem shows how complex the strange loop really is. He argues that Goedel’s theorem is about self-reference in a symbol system, and how that enables self-reference in general, and more specifically the kind of self-perception that makes a person. You can skip this part of the book.
His motivation for this extended meditation on the self was the death of his wife. Like many people who have lost a most-beloved one, he had the uncanny feeling that she was still in some sense present, within himself, in his memories of her, in which he re-enacted how she would have responded to a new piece of music, to a new book, to a walk in a well-loved wood. In a sense, her personality was stored within him, and trying to puzzle that out led him back to the central question of his life. I don’t think you should skip those parts of the book.
I thoroughly enjoyed this book. Recommended. ****
See also my review of Rosenfield's The Strange, Familiar and Forgotten.
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