Online research in philosophy

Paul Churchland has become famous for holding three controversial and interrelated doctrines which he put forward in early papers and in his first book. Scientific Realism and the Plasticity of Mind (1979): eliminative materialism, the doctrine of the plasticity of perception, and a general network theory of language. In his latest book, The Engine of Reason, the Seat of the Soul (1995), Churchland aims to make some results of connectionist neuroscience available to the general public and explores the philosophical and social consequences that neuroscience is likely to have. I argue that these results of neuroscience refute the three doctrines that Churchland advocated in his earlier works. Yet youthful dreams do not die easily and Churchland is reluctant to relinquish his early views.

This paper critically examines Jerry Fodor's latest attacks on evolutionary psychology. Contra Leda Cosmides and John Tooby, Fodor argues (i) there is no reason to think that human cognition is a Darwinian adaptation in the first place, and (ii) there is no valid inference from adaptationism about the mind to massive modularity. However, Fodor maintains (iii) that there is a valid inference in the converse direction, from modularity to adaptationism, but (iv) that the language module is an exception to the validity of this inference. I explore Fodor's arguments for each of these claims, and the interrelations between them. I argue that Fodor is incorrect on point (i), correct on point (ii), partially correct on point (iii), and incorrect on point (iv). Overall, his critique fails to show that adopting a broadly Darwinian approach to cognition is intellectually indefensible.

It is very tempting to try to reconcile perception and cognition perceptual symbol systems may be a good way to achieve this; but is there actually a perception-cognition continuum? We offer several arguments for and against the existence of such a continuum and in favor of the choice of perceptual symbol systems. One of these arguments is purely theoretical, some are based on PET-scan observations and others are based on research with handicapped subjects who have communication problems associated with cerebral lesions. These arguments suggest that modal perceptual symbols do indeed exist and that perception and cognition might have a common neuronal basis; but perceptual and cognitive activities require the activation of different neuronal structures.

Jerry Fodor's Asymmetric Dependency Theory (ADT) of meaning is discussed in the context of his attempt to avoid holism and the relativism it entails. Questions are raised about the implications of the theory for psychological theories of meaning, and brief suggestions are offered for how to more closely link a theory of meaning to a theory of perception.

The aim of this paper is to analyze a philosophical question (neutrality vs. theory-ladenness of observation) taking into consideration the empirical results of Cognitive Psychology (theories of perception). This is an important debate because the objectivity of science is at stake. In the Philosophy of Science there are two main positions with regard to observation, those of C. Hempel and N. R. Hanson. In the Philosophy of Mind there are also two important contrasting positions, those of J. Fodor and Paul M. Churchland. I will analyze the consequences of recent theories of perception and vision developed within Cognitive Science for classical epistemological theses about observation.

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.

In this paper I argue that because Churchland does not adequately address the distinction between high-level cognitive theories and low-level embodied theories, Churchland's claims for theory-laden perception lose their epistemological significance. I propose that Churchland and others debating the theory-ladenness of perception should distinguish carefully between two main ways in which perception is plastic: through modifying our high-level theories directly and through modifying our low-level theories using training experiences. This will require them to attend to two very different types of constraints on the modification of our perceptions.

The basic problem of perceptual change is how to account for both variation and constancy in perceiving the world. Is order learned? How deep does plasticity go in that respect? I argue that different kinds of perceptual plasticity have been confused in recent debates, notably between J. Fodor and P. M. Churchland. By focusing on changes in the use of concepts, the issues in the Fodor-Churchland debate can be resolved. Beyond that debate, I propose a generalized encoding approach to perception as a way of accounting for a significant form of perceptual change.

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.