In this paper I offer a novel analysis of Quine's indeterminacy puzzle and an unorthodox approach to its resolution. It is argued that the ultimate roots of indeterminacy lie not in behaviorism per se, but rather in Quine's commitment to a fundamental assumption about the nature of perceptual input, namely, the assumption that sensory information is strictly extensional. Calling this assumption the 'principle of input extensionalism' (PIE) I first demonstrate the fundamental role that it plays in generating Quine's argument for (...) the indeterminacy of translation. It is then argued that a tacit acceptance of PIE is prevalent among contemporary theories of cognition and representation, making Quine's puzzle a living challenge for cognitive science and the philosophy of mind. A standard way of responding to the challenge consists of the idea that the indeterminacy generated at the perceptual level is canceled out courtesy of the contribution of higher cognitive processes. However, I argue that such a top-down solution leaves much to be desired. As an alternative, I offer a bottom-up solution, which consists of a systematic rejection of PIE in favor of an intensional view of perceptual input rooted in contemporary action-based theories of perception, and in particular in the notion of perceptual invariants. (shrink)

Abstract“Sign stimuli” elicit specific patterns of behavior when an organism's motivation is appropriate. In the toad, visually released prey-catching involves orienting toward the prey, approaching, fixating, and snapping. For these action patterns to be selected and released, the prey must be recognized and localized in space. Toads discriminate prey from nonprey by certain spatiotemporal stimulus features. The stimulus-response relations are mediated by innate releasing mechanisms (RMs) with recognition properties partly modifiable by experience. Striato-pretecto-tectal connectivity determines the RM's recognition and localization (...) properties, whereas medialpallio-thalamo-tectal circuitry makes the system sensitive to changes in internal state and to prior history of exposure to stimuli. RMs encode the diverse stimulus conditions referring to the same prey object through different combinations of “specialized” tectal neurons, involving cells selectively tuned to prey features. The prey-selective neurons express the outcome of information processing in functional units consisting of interconnected cells. Excitatory and inhibitory interactions among feature-sensitive tectal and pretectal neurons specify the perceptual operations involved in distinguishing the prey from its background, selecting its features, and discriminating it from predators. Other connections indicate stimulus location. The results of these analyses are transmitted by specialized neurons projecting from the tectum to bulbar/spinal motor systems, providing a sensorimotor interface. Specific combinations of such projective neurons – mediating feature- and space-related messages – form “command releasing systems” that activate corresponding motor pattern generators for appropriate prey-catching action patterns. (shrink)

Philosophical controversy about the mind has flourished in the thin air of our ignorance about the brain. The humble toad, it now seems, may provide our first instance of a creature whose whole brain is within the reach of our scientific understanding. What will happen to the traditional philosophical issues as our theoretical and factual ignorance recedes? Discussion of the issues explored in the target article is, as Ewert says, "often too theoretical, sometimes philosophical and even [as if that weren't (...) bad enough?--DCD] emotion-laden." The research reported by Ewert has interesting philosophical implications, as he probably recognizes, but he wisely leaves the philosophy to the philosophers. Being one, I would like to draw some of the conclusions he eschews. (shrink)

Cognitive niche theories consist in a theoretical framework that is proving extremely profitable in bridging evolutionary biology, philosophy, cognitive science, and anthropology by offering an inter-disciplinary ground, laden with novel approaches and debates. At the same time, cognitive niche theories are multiple, and differently related to niche theories in theoretical and evolutionary biology. The aim of this paper is to clarify the theoretical and epistemological relationships between cognitive and ecological niche theories. Also, by adopting a constructionist approach we will try (...) to explain the shift from ecological to cognitive niches and their actual and theoretical overlaps. In order to do so, we will take two concepts expressing loose forms of causation in the interaction between organisms and their environment: the biological notion of “enablement” and the psycho-cognitive one of “affordance”. (shrink)