Words, Thoughts, and Theories

1. The Other Socratic Method

• The child treats the adult language as another source of information about the structure of the world, along with her own experience. While the child is inferring the structure of the outside world, she is also untangling the structure of language itself, and she may use solutions in one area as clues to solutions in the other.
• Ultimately, our motivation for watching and talking to children is the same as Socrates'. The most central questions in cognitive science are questions that only they can answer.

I: The Theory Theory

2. The Scientist as Child

• Science is cognitive almost by definition, insofar as cognition is about how minds arrive at veridical conceptions of the world.
• A cognitive view of science might provide a useful middle ground, even a bridge, between logical and sociological views of science.
• Quite typically, underlying any human cognitive activity is an abstract structure that is not at all apparent in superficial phenomenology or practice.
• From an evolutionary point of view, three of the most distinctive features of human beings are their long, protected immaturity, the plasticity of their behavior, and their ability to adapt to an extremely wide variety of environments. Equipping human children with particularly powerful and flexible cognitive devices might be an important part of this picture. Indeed, we might think of childhood as a period when many of the requirements for survival are suspended so that children can concentrate on acquiring a veridical picture of the particular physical and social world in which they find themselves.
• Once, as children, we have engaged in the theorizing necessary to specify the features of our world, most of us most of the time may simply go on to the central evolutionary business of feeding and reproducing. But, we suggest, these powerful theorizing abilities continue to allow all of us some of the time and some of us, namely professional scientists, much of the time to continue to discover more and more about the world around us.
• A characteristic lesson of the cognitive revolution is that human beings (or, for that matter, machines) can perform extremely complex feats of information processing without any phenomenology at all. It is rather characteristic of human cognition that it is largely inaccessible to conscious reflection.
• Children, no less than scientists, develop their understanding of the world in the context of a society that already has much knowledge of the world. they live in a rich social structure with much opportunity for contradiction, instruction, and the linguistic transmission of information.
• We might argue that much of the social structure of science is an attempt to replicate the privileged sociological conditions of infancy. Aside from the division of labor, the social hierarchy largely determines who will get the leisure and equipment to do cognitive work and who other scientists should listen to. The infant solves these problems without needing elaborate social arrangements.
• What happens when the theorizing mechanisms are faced with a causal problem but have no relevant evidence to operate on? What happens, we suggest, is magic, a combination of narrative, deference, and association.
• In the course of developing an account of the mind, children postulate such mental entities as perceptions, beliefs, and desires as a way of explaining ordinary human behavior.
• It is not that children are little scientists but that scientists are big children. Scientific progress is possible because scientists employ cognitive processes that are first seen in very young children.

Theories:

• Are always constructed with reference to evidence.
• Include entities and laws that are postulated or recruited from elsewhere to explain evidence.
• The entities postulated by a theory are closely, "lawfully", interrelated with one another.
• Appeal to some underlying causal structure that we think is responsible for the superficial regularities in the data.
• An accepted theory is supposed to carve nature at its joints; the theoretical entities and laws are supposed to tell you what there is and what it must do.
• A test of theoreticity is the nature of our surprise at violations of the theory. If we are committed to the theory, such violations should strike us not only as surprising but as being impossible and unbelievable in an important and strong way.
• A theory, in contrast to a mere empirical generalization, makes predictions about a wide variety of evidence, including evidence that played no role in the theory's initial construction
• The ability to produce wide-ranging predictions is perhaps the most obvious pragmatic benefit of science, and it may also be the most important evolutionary benefit of developing theorizing abilities. The evolutionary value of a system that leads to accurate and wide-ranging predictions should be obvious. In fact, making accurate predictions about the behavior of the world and your fellow organisms is the sine qua non of cognition.
• Theories produce interpretations of evidence, not simply descriptions and typologies of it. Indeed, theories strongly influence which pieces of evidence we consider salient or important. Theory-driven interpretations help to solve what computer scientists call "the frame problem". Theories provide a way of deciding which evidence is relevant to a particular problem
• What we mean by saying that we've explained something is simply that we can give an abstract, coherent, causal account of it. We might say that explanation is to cognition as orgasm is to reproduction.
• We might speculate that we were designed with a theorizing drive and that explanation is a symptom of that drive in action.
• Theories may turn out to be inconsistent with the evidence, and because of this theories change. In fact a tenet of modern epistemology is that any aspect of a theory, even the most central ones, may change.
• The initial reaction of a theory to counter-evidence may be a kind of denial. The interpretive mechanisms of the theory may treat the counter-evidence as noise, mess, not worth attending to. At a slightly later stage, the theory may develop ad hoc auxiliary hypotheses designed to account specifically for such counter-evidence. The theory gets ugly and messy instead of being beautiful and simple. The preference for beautiful theories over ugly ones plays an additional major role in theory change.
• A next step requires an alternative model to the original theory. The theory may limp along for some time under the weight of its auxiliary hypotheses if no alternative way of making progress is available. The ability to fix on this alternative is the mysterious logic of discovery.
• The new idea is not simply the olde idea applied to a new domain, but rather the earlier idea is itself modified to fit its role in the new theory. Moreover the fertility of the alternative idea may not be immediately recognized. Initially it may be applied only to the problematic cases.
• A final important dynamic feature of theory formation is a period of intense experimentation and/or observation. This period might span both the crisis of the earlier theory (when anomalous results are being produced right and left) and the first stages of the new theory (when a whole range of new predictions become available).
• In the development of the heliocentric theory of the planets:
  • Auxiliary hypotheses involving more and more complex arrangements of epicycles were initially invoked to deal with counterevidence
  • Later heliocentrism was introduced by Copernicus, but it continued to rely on epicycles as an auxiliary hypothesis.
  • Tycho Brahe's account acknowledges many of the flaws of the Ptolemaic accounts and uses the ides of heliocentrism to deal with them, but fails to accept the central idea that the earth itself goes around the sun.
  • Only with Kepler is there a really coherent heliocentric account that deals both with the anomalies and with the earlier data itself. And while, strictly speaking, experimentation on the heavenly bodies was impossible, periods of intense and detailed observation in this transitional period provided a far richer empirical base than had been available before.