Fuzziness of concepts and concepts of fuzziness

It has been a vexing question in recent years whether concepts are fuzzy. In this paper several views on the fuzziness of concepts are pointed out to have stemmed from dubious concepts of fuzziness. The underlying notions of the roles feasibly played byprototype, set, andprobability in modeling concepts strongly suggest that the controversy originates from a vague relation between intuitive and mathematical ideas in the cognitive sciences. It is argued that the application of fuzzy sets cannot resolve this vagueness since they are one sided,viz., defined on sets. An alternative definition based on classes (in the sense of axiomatic set theory) is proposed.     

Comparative concepts

Comparative concepts such as greener than or higher than are ways of ordering objects. They are fundamental to our grasp of gradable concepts, that is, the type of meanings expressed by gradable general terms, such as ??is green?? or ??is high??, which are embeddable in comparative constructions in natural language. Some comparative concepts seem natural, whereas others seem gerrymandered. The aim of this paper is to outline a theoretical approach to comparative concepts that bears both on the account of naturalness for comparative concepts and on the theory of gradable concepts. The approach is novel in that it carries some basic assumptions from Peter G?rdenfors?? conceptual spaces account of categorical concepts over to comparative concepts. The offered approach is more general than G?rdenfors?? account in that it supplies a framework of graded categorisation that includes his categorisation rule as a limiting case. Importantly, it provides also a new argument for adopting G?rdenfors?? particular model of categorisation.     

Clinical concepts

In this section authors have written about the Winnicottian concept that they value most in their everyday working lives. This provides a valuable insight into the ways in which Winnicott's work is being used as a springboard for new ideas, as well as enlightening familiar ground. It is striking to see how the original Winnicottian idea takes on new form as it is taken up by new generations of clinicians. Despite the absence of a Winnicottian training school, his pervasive impact continues to influence current theory and practice.     

Disjunction of natural concepts

Two experiments investigated the way in which the rated membership of items in disjunctively defined categories, such as FRUITS OR VEGETABLES and PETS OR FARMYARD ANIMALS, varies as a function of membership in individual constituent categories. Items were rated for category membership and typicality in each category separately, and in their disjunction. The results showed non-Boolean effects of both overextension and underextension of the disjunctions. Typicality in the disjunction was highly predictable from constituent typicality values, using regression equations with negative interaction terms. The results are compared with similar effects for concept conjunctions and are discussed in terms of an intensional model of conceptual combination (Hampton, 1987b, 1988).     

The origins of concepts

Certain of our concepts are innate, but many others are learned. Despite the plausibility of this claim, some have argued that the very idea of concept learning is incoherent. I present a conception of learning that sidesteps the arguments against the possibility of concept learning, and sketch several mechanisms that result in the generation of new primitive concepts. Given the rational considerations that motivate their deployment, I argue that these deserve to be called learning mechanisms. I conclude by replying to the objections that these mechanisms cannot produce genuinely new content and cannot be part of genuinely cognitive explanations.

The plurality of concepts

Traditionally, theories of concepts in psychology assume that concepts are a single, uniform kind of mental representation. But no single kind of representation can explain all of the empirical data for which concepts are responsible. I argue that the assumption that concepts are uniformly the same kind of mental structure is responsible for these theories’ shortcomings, and outline a pluralist theory of concepts that rejects this assumption. On pluralism, concepts should be thought of as being constituted by multiple representational kinds, with the particular kind of concept used on an occasion being determined by the context. I argue that endorsing pluralism does not lead to eliminativism about concepts as an object of scientific interest.