Figure It Out. Stephen P. Anderson

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СКАЧАТЬ people can adapt to such a bizarre visual experience is surprising. Hence the hundreds of studies to explore the phenomenon. More surprising is that if the person remains stationary, they do not adapt. If they don’t walk, or they are handed objects instead of reaching for them, their brain doesn’t reconfigure itself to this new way of seeing.⁴ Furthermore, when people take off the glasses in these stationary studies, they readapt immediately, without any dizziness or other adverse symptoms.

      Our brain is astonishing. Our perceptual abilities are magnificent, especially our visual perception. But our bodies matter, too, often more than we realize. Action changes the brain and how we interpret information in the world. Yet the modern story of the brain is largely about what happens in our head. We are told the brain is a kind of biological supercomputer. That three-pound lump of squishy goo, nestled in our skull, is the engine that drives our ability to think, reason, decide, plan, and make sense of the world around us. That’s the standard story and so, as a result, we tend to view the world as out there (beyond the head) and understanding is in here (inside the head). Although the brain remains supremely important, there is more to the story, as the Stratton effect suggests.

      The Stratton effect brings to mind an aphorism, often attributed to Confucius, sometimes as just an old Chinese proverb, that goes “I hear and I forget, I see and I remember, I do and I understand.” It’s a reminder of the connection between doing and understanding, and how acting in the world shapes our ability to make sense of it. In the pages that follow, we will see how the science of mind is evolving in a direction that echoes Confucius, though, of course, as always with science, it’s somewhat more complicated than something you can print on a t-shirt. Our purpose in this chapter is to wrap our arms around this new science of mind and, from that, develop a foundation for how the information in our world can help us become better thinkers. Let’s start there, with a question: How does the mind work?

      Behaviorism and the Cognitive Revolution

      Since the days of Socrates and Plato, and almost certainly before then, human beings have wondered how we think, understand, and gain knowledge about the world we inhabit. The modern quest for a theory of mind began with the emergence of cognitive science in the late 1950s. Back then, the dominant theory was behaviorism, which viewed the brain as a black box—a biological device whose inner workings could never be directly observed. Because there was no way to see an idea, or a thought, or anything that happened in the head, behaviorists were taught “to eschew such topics as mind, thinking, or imagination and such concepts as plans, desires, or intentions.”⁵ What happened in the brain was mysterious and unknowable and, therefore, off limits.

      Not everyone was convinced. Some researchers believed that clever experiments could be devised that would explain the machinery of mind, at least in part. Early experiments were promising, many more were undertaken, and the cognitive revolution was underway. By the 1990s, cognitive science had convincingly demolished the central premise of behaviorism: the machinery of mind was knowable. Harvard psychologist Steven Pinker summarized the cognitive turn this way: “Behaviorists insisted that all talk about mental events was sterile speculation ... Exactly the opposite turned out to be true.”⁶

      Cognitive science came to see the mind as an elaborate biological apparatus for processing information. It starts with your senses, which perceive information from the world and send signals to your brain. When you stub your toe, for example, information passes from the nerve ending, through the spinal cord, and up to your brain. When the stoplight turns green, your eyes perceive this change and send the information along the optic nerve. Your brain takes these signals and converts them into symbols. Cognitive scientists call these symbols mental representations, which is simply a scientific phrase that means thoughts or ideas. The brain processes these representations, transforming them into other representations, and the whole operation is what we call cognition. Originally known as the information-processing theory, today it is often called the computational theory of mind.

      Thus, cognitive science is based on two fundamental concepts: mental representation and mental computation. The term computation, however, requires some qualification. To say the mind does computation does not mean the neurons in your brain work just like the silicon transistors in your laptop. Rather, it means that we can explain how brains and computers operate using many of the same principles, even though the details are vastly different. Pinker provides a useful analogy: “To explain how birds fly, we invoke principles of lift and drag and fluid mechanics that also explain how airplanes fly. That does not commit us to an airplane metaphor for birds, complete with jet engines and complimentary beverage service.”⁷ This view of the mind does, however, hinge on the conviction that brains do perform computation, in some way, on mental representations.

      The Computational Theory of Mind

      The computational theory of mind has a straightforward model of cognition built around four parts: the external world, perception, cognition, and action. These form a loop, as shown in Figure 2.1. Under this model, we perceive information from the world through our senses, which our brain converts into mental representations. This is followed by cognition proper (mental computation on mental representations), which, in turn, leads to acting on the world. Then the cycle begins anew with more perception, cognition, action, and so forth.

FIGURE 2.1 The basic structure of human cognition according to the computational theory of mind. Although grossly simplified, it captures the essential features of the standard model.

      The most notable features of this model are that it’s sequential—first one thing, then another—and that cognition happens in the head. Perception serves as the input to cognition, and the output is action on the world. The starring role in the cognitive drama goes to brain-based processes (i.e., mental computation). Anything that happens outside the skull is secondary, merely part of the supporting cast.

      This brain-centered view of human thinking forms the foundation for many models of human cognition. One of the most influential models is the Model Human Processor, which was developed in the early 1980s as the cognitive revolution was in full swing. This model divides the mind into three main parts: perception (for converting sensory input into mental representations), cognition (for mental computation and memory), and motor control (for moving the body).⁸ In other words, perception is input, cognition happens in the brain, and action is output, just like the diagram in Figure 2.1.

      Other cognitive models share a similar structure. Consider EPIC, which was developed to model how human beings interact with computers.⁹ Like the Model Human Processor, EPIC is also based on input and output mechanisms (see Figure 2.2). It describes the human body in terms so comically detached from everyday life that you can almost see the lab coats and pocket protectors.

FIGURE 2.2 The EPIC model of cognition: note how the terminology describes parts of the body in terms of inputs, outputs, and processing information. The model also omits many parts of the body—legs and feet being the most obvious.

      It features an “auditory processor” instead of ears, a “vocal motor processor” instead of a mouth, and an “ocular motor processor” instead of eyes. Hands are called manual motor processors and, in an oversight that reflects a world before smartphones, the modeled human has no feet.

      Where СКАЧАТЬ