In this 1958 book, Professor Hanson turns to an equally important but comparatively neglected subject, the philosophical aspects of research and discovery.

A scientific community cannot practice its trade without some set of received beliefs. These beliefs form the foundation of the "educational initiation that prepares and licenses the student for professional practice". The nature of the "rigorous and rigid" preparation helps ensure that the received beliefs are firmly fixed in the student's mind. Scientists take great pains to defend the assumption that scientists know what the world is like...To this end, "normal science" will often suppress novelties which undermine its foundations. Research (...) is therefore not about discovering the unknown, but rather "a strenuous and devoted attempt to force nature into the conceptual boxes supplied by professional education". (shrink)

Thomas S. Kuhn's classic book is now available with a new index.

We have been discussing some of the fundamental features of the classical calculus of probability. The equiprobability of rival events was seen to be a major assumption of the calculus. Moreover, it is an assumption which the pure mathematician need not bother to justify. He need only present his formal system as follows.

What is the Moral Problem? NORMATIVE ETHICS VS. META-ETHICS It is a common fact of everyday life that we appraise each others' behaviour and attitudes from ...

In this paper I argue that it's possible that the contents of some visual experiences are influenced by the subject's prior beliefs, hopes, suspicions, desires, fears or other mental states, and that this possibility places constraints on the theory of perceptual justification that 'dogmatism' or 'phenomenal conservativism' cannot respect.

In this paper I argue for the cognitive impenetrability of perception by undermining the argument from reentrant pathways. To do that I will adduce psychological and neuropsychological evidence showing that (a) early vision processing is not affected by our knowledge about specific objects and events, and (b) that the role of the descending pathways is to enable the early-vision processing modules to participate in higher-level visual or cognitive functions. My thesis is that a part of observation, which I will call (...) perception, is bottom-up and theory neutral. As such, perception could play the role of common ground on which a naturalized epistemology can be built and relativism avoided. (shrink)

Although the study of visual perception has made more progress in the past 40 years than any other area of cognitive science, there remain major disagreements as to how closely vision is tied to general cognition. This paper sets out some of the arguments for both sides and defends the position that an important part of visual perception, which may be called early vision or just vision, is prohibited from accessing relevant expectations, knowledge and utilities - in other words it (...) is cognitively impenetrable. That part of vision is complex and articulated and provides a representation of the 3-D surfaces of objects sufficient to serve as an index into memory, with somewhat different outputs being made available to other systems such as those dealing with motor control. The paper also addresses certain conceptual and methodological issues, including the use of signal detection theory and event-related potentials to assess cognitive penetration of vision. A distinction is made among several stages in visual processing. These include, in addition to the inflexible early-vision stage, a pre-perceptual attention allocation stage and a post-perceptual evaluation, memory-accessing, and inference stage which provide several different highly constrained ways in which cognition can affect the outcome of visual perception. The paper discusses arguments that have been presented in both computer vision and psychology showing that vision is "intelligent" and involves elements of problem solving". It is suggested that these cases do not show cognitive penetration, but rather they show that certain natural constraints on interpretation, concerned primarily with optical and geometrical properties of the world, have been compiled into the visual system. The paper also examines a number of examples where instructions and "hints" are alleged to affect. (shrink)

I assess Churchland's views on folk psychology and conceptual thinking, with particular emphasis on the connection between these topics.

The proposition that perception is in- fluenced by object value and perceiver need has enjoyed an exciting career since it was given prominence by Bruner and Goodman in an oral and, later, a printed report (3) of dramatic differ- ences between rich and poor children in their judgments of coin sizes. Whether that study or subsequent ones can be said to have upheld the proposition may be questionable; but the effect on psy- chologists is beyond doubt. They were refreshed and (...) stimulated. The ideas, the experimental approach, and the re- sults were new, and quite obviously ap- pealed to current needs. (shrink)

Can the phenomenal character of perceptual experience be altered by the states of one's cognitive system, for example, one's thoughts or beliefs? If one thinks that this can happen then one thinks that there can be cognitive penetration of perceptual experience; otherwise, one thinks that perceptual experience is cognitively impenetrable. I claim that there is one alleged case of cognitive penetration that cannot be explained away by the standard strategies one can typically use to explain away alleged cases. The case (...) is one in which it seems subjects' beliefs about the typical colour of objects affects their colour experience. I propose a two-step mechanism of indirect cognitive penetration that explains how cognitive penetration may occur. I show that there is independent evidence that each step in this process can occur. I suspect that people who are opposed to the idea that perceptual experience is cognitively penetrable will be less opposed to the idea when they come to consider this indirect mechanism and that those who are generally sympathetic to the idea of cognitive penetrability will welcome the elucidation of this plausible mechanism. (shrink)

Norwood Russell Hanson was one of the most important philosophers of science of the post-war period. Hanson brought Wittgensteinian ordinary language philosophy to bear on the concepts of science, and his treatments of observation, discovery, and the theory-ladenness of scientific facts remain central to the philosophy of science. Additionally, Hanson was one of philosophy's great personalities, and his sense of humor and charm come through fully in the pages of Perception and Discovery. Perception and Discovery, originally published in 1969, is (...) Hanson's posthumous textbook in philosophy of science. The book focuses on the indispensable role philosophy plays in scientific thinking. Perception and Discovery features Hanson's most complete and mature account of theory-laden observation, a discussion of conceptual and logical boundaries, and a detailed treatment of the epistemological features of scientific research and scientific reasoning. This book is of interest to scholars of philosophy of science, particularly those concerned with Hanson's thought and the development of the discipline in the middle of the 20th century. However, even fifty years after Hanson's early death, Perception and Discovery still has a great deal to offer all readers interested in science. (shrink)

Norwood Russell Hanson was one of the most important philosophers of science of the post-war period. Hanson brought Wittgensteinian ordinary language philosophy to bear on the concepts of science, and his treatments of observation, discovery, and the theory-ladenness of scientific facts remain central to the philosophy of science. Additionally, Hanson was one of philosophy’s great personalities, and his sense of humor and charm come through fully in the pages of Perception and Discovery. Perception and Discovery, originally published in 1969, is (...) Hanson’s posthumous textbook in philosophy of science. The book focuses on the indispensable role philosophy plays in scientific thinking. Perception and Discovery features Hanson’s most complete and mature account of theory-laden observation, a discussion of conceptual and logical boundaries, and a detailed treatment of the epistemological features of scientific research and scientific reasoning. This book is of interest to scholars of philosophy of science, particularly those concerned with Hanson’s thought and the development of the discipline in the middle of the 20th century. However, even fifty years after Hanson’s early death, Perception and Discovery still has a great deal to offer all readers interested in science. (shrink)

Several arguments are considered which purport to demonstrate the impossibility of theory-neutral observation. The most important of these infers the continuity of observation with theory from the presumed continuity of perception with cognition, a doctrine widely espoused in recent cognitive psychology. An alternative psychological account of the relation between cognition and perception is proposed and its epistemological consequences for the observation/theory distinction are then explored.

The Modularity of Mind proposes an alternative to the or view of cognitive architecture that has dominated several decades of cognitive science. Whereas interactionism stresses the continuity of perceptual and cognitive processes, modularity theory argues for their distinctness. It is argued, in particular, that the apparent plausibility of New Look theorizing derives from the failure to distinguish between the (correct) claim that perceptual processes are inferential and the (dubious) claim that they are unencapsidated, that is, that they are arbitrarily sensitive (...) to the organism's beliefs and desires. In fact, according to modularity theory, perceptual processes are computationally isolated from much of the background knowledge to which cognitive processes have access. The postulation of autonomous, domain-specific psychological mechanisms underlying perceptual integration connects modularity theory with the tradition of faculty psychology, in particular, with the work of Franz Joseph Call. Some of these historical affinities, and some of the relations between faculty psychology and Cartesianism, are discussed in the book. (shrink)

Churchland's paper "Perceptual Plasticity and Theoretical Neutrality" offers empirical, semantical and epistemological arguments intended to show that the cognitive impenetrability of perception "does not establish a theory-neutral foundation for knowledge" and that the psychological account of perceptual encapsulation that I set forth in The Modularity of Mind "[is] almost certainly false". The present paper considers these arguments in detail and dismisses them.

A study in the philosophy of science, proposing a strong form of the doctrine of scientific realism' and developing its implications for issues in the philosophy of mind.

The present essay is addressed simultaneously to two distinct audiences.

The doctrine that the character of our perceptual knowledge is plastic, and can vary substantially with the theories embraced by the perceiver, has been criticized in a recent paper by Fodor. His arguments are based on certain experimental facts and theoretical approaches in cognitive psychology. My aim in this paper is threefold: to show that Fodor's views on the impenetrability of perceptual processing do not secure a theory-neutral foundation for knowledge; to show that his views on impenetrability are almost certainly (...) false; and to provide some additional arguments for, and illustrations of, the theoretical character of all observation judgments. (shrink)

A Neurocomputationial Perspective illustrates the fertility of the concepts and data drawn from the study of the brain and of artificial networks that model the...

We use evidence from cognitive psychology and the history of science to examine the issue of the theory-ladenness of perceptual observation. This evidence shows that perception is theory-laden, but that it is only strongly theory-laden when the perceptual evidence is ambiguous or degraded, or when it requires a difficult perceptual judgment. We argue that debates about the theory-ladenness issue have focused too narrowly on the issue of perceptual experience, and that a full account of the scientific process requires an examination (...) of theory-ladenness in attention, perception, data interpretation, data production, memory, and scientific communication. We conclude that the evidence for theory-ladenness does not lead to a relativist account of scientific knowledge. (shrink)

This study synthesizes current information from the various fields of cognitive science in support of a new and exciting theory of mind. Most psychologists study horizontal processes like memory and information flow; Fodor postulates a vertical and modular psychological organization underlying biologically coherent behaviors. This view of mental architecture is consistent with the historical tradition of faculty psychology while integrating a computational approach to mental processes. One of the most notable aspects of Fodor's work is that it articulates features not (...) only of speculative cognitive architectures but also of current research in artificial intelligence. (shrink)

To desire something is a condition familiar to everyone. It is uncontroversial that desiring has something to do with motivation, something to do with pleasure, and something to do with reward. Call these "the three faces of desire." The standard philosophical theory at present holds that the motivational face of desire presents its unique essence--to desire a state of affairs is to be disposed to act so as to bring it about. A familiar but less standard account holds the hedonic (...) face of desire to reveal to true nature of desire. In this view, to desire something is to tend to pleasure if it seems that the desired state of affairs has been achieved, or displeasure if it seems otherwise, thus tying desire to feelings instead of actions. In Three Faces of Desire, Schroeder goes beyond actions and feelings to advance a novel and controversial theory of desire that puts the focus on desire's neglected face, reward. Informed by contemporary science as much as by the philosophical tradition, Three Faces of Desire discusses recent scientific discoveries that tell us much about the way that actions and feelings are produced in the brain. In particular, recent experiments reveal that a distinctive system is responsible for promoting action, on the one hand, and causing feelings of pleasure and displeasure, on the other. This system, the brain's reward system, is the causal origin of both action and feeling, and is the key to understanding the nature of desire. (shrink)

This systematic investigation of computation and mental phenomena by a noted psychologist and computer scientist argues that cognition is a form of computation, that the semantic contents of mental states are encoded in the same general way as computer representations are encoded. It is a rich and sustained investigation of the assumptions underlying the directions cognitive science research is taking. 1 The Explanatory Vocabulary of Cognition 2 The Explanatory Role of Representations 3 The Relevance of Computation 4 The Psychological Reality (...) of Programs: Strong Equivalence 5 Constraining Functional Architecture 6 The Bridge from Physical to Symbolic: Transduction 7 Functional Architecture and Analogue Processes 8 Mental Imagery and Functional Architecture 9 Epilogue: What is Cognitive Science the Science of? (shrink)