3 results
5 - Availability in Category-Based Induction
- Edited by Aidan Feeney, University of Durham, Evan Heit, University of Warwick
-
- Book:
- Inductive Reasoning
- Published online:
- 26 February 2010
- Print publication:
- 03 September 2007, pp 114-136
-
- Chapter
- Export citation
-
Summary
Induction can be supported by many kinds of knowledge. To be effective, reasoning should be context sensitive; different kinds of knowledge should be selectively deployed in different situations. For example, in the domain of biology, when reasoning about the distribution of novel internal properties over species, taxonomic knowledge should be recruited since we know that taxonomic membership is not only related to perceptual similarity but is also a good predictor of shared unobservable anatomical features such as four-chambered hearts. However, when reasoning about the distribution of environmental toxins, ecological knowledge should be recruited since such a toxin would plausibly spread through an ecosystem. In this chapter, we address the factors that influence the recruitment of different kinds of knowledge in different contexts. We propose that different kinds of knowledge are differentially available across contexts. Using this concept of availability, we will address an array of experimental results, arguing for availability as a way to unite and explain a broad range of phenomena in category-based induction.
In a classic paper, Tversky and Kahneman (1973) discuss availability as a heuristic “by which people evaluate the frequency of classes or the likelihood of events” (p. 207). This involves estimating frequency or probability “by the ease with which instances or associations are brought to mind” (p. 208). As such, availability on this view is essentially a metacognitive heuristic by which information is judged more likely or plausible based on an estimate of the effort involved in retrieving the information; indeed, Tversky and Kahneman argue that “to assess availability it is not necessary to perform the actual operations of retrieval or construction. It suffices to assess the ease with which these operations could be performed” (p. 208).
13 - Essentialist beliefs in children: The acquisition of concepts and theories
- Edited by Lawrence A. Hirschfeld, University of Michigan, Ann Arbor, Susan A. Gelman, University of Michigan, Ann Arbor
-
- Book:
- Mapping the Mind
- Published online:
- 04 August 2010
- Print publication:
- 29 April 1994, pp 341-366
-
- Chapter
- Export citation
-
Summary
In their first few years of life, children are making sense of the world at two levels at once: at the fine-grained level of everyday object categories (deciding which things are trees and which are dogs and which are cookies), and at a broader level that some have called commonsense “theories.” Both are remarkable achievements. First, consider categorization. If children's vocabulary is any indication, by the age of 6 they have carved up the world into thousands of distinct categories (Carey, 1978). Many children undergo a vocabulary “explosion” at roughly 18 months of age (Halliday, 1975; McShane, 1980; Nelson, 1973), when the rate of acquisition suddenly rises exponentially. One child studied in detail by Dromi (1987) produced as many as 44 new words in one week, and roughly 340 new words in her first 7 months of speech. No other species acquires symbolic communication at this rate. Even studies that successfully teach apes to acquire sizeable vocabularies in sign language are incomparable, with no noticeable vocabulary explosion (e.g., after more than 4 years of exposure to sign language, Washoe acquired only about 132 signs; Gardner & Gardner, 1989).
At around the same time that children learn to classify individual entities and undergo rapid vocabulary growth, they are developing broad systems of belief about the world. Not only do children learn to identify certain objects as “dogs,” but they also learn that dogs belong to the class of animals, and that animals engage in characteristic biological processes such as growth, inheritance, and self-generated movement. Children are learning about physical laws such as gravity, mental states such as dreams, and social relationships within units such as families.
5 - Language and categorization: The acquisition of natural kind terms
-
- By Susan A. Gelman, University of Michigan, John D. Coley, University of Michigan
- Edited by Susan A. Gelman, James P. Byrnes
-
- Book:
- Perspectives on Language and Thought
- Published online:
- 05 January 2012
- Print publication:
- 25 October 1991, pp 146-196
-
- Chapter
- Export citation
-
Summary
What is striking about human categories is their diversity. They range from the simplest classification of a face or color to the most carefully constructed taxonomic grouping. Considering this diversity, many are struck by the apparent gap between the simple, intuitive categories formed by children and the complex, theory-laden categories of educated adults (e.g., Inhelder & Piaget, 1964; Quine, 1969; Vygotsky, 1962).
In this chapter we first argue that despite a number of salient differences between children's categories and those of adults, there are important parallels between the two: Both are informed by an ability to overlook salient appearances, an attention to nonobvious properties, and the potential to draw many new inferences about the unknown. Both the initial groupings of the prescientific child and the most thoughtful, theory-laden classifications of the adult extend knowledge in important ways. To use Quine's terminology, both children and adults form “theoretical kinds.” Second, we address the role of language in the formation of theoretical kinds. Although the structure of everyday object categories (e.g., dog, hammer, oak tree, and computer) is traditionally thought to result from the structure of the world and/or the nature of human perception and cognition, we will present evidence that language is also critical and that how objects are named helps determine the structure of the categories they fall into.
The chapter has three sections. In the first, we set forth our assumptions about the nature of categories for adults. We review recent analyses suggesting that categories are enriched and informed by intuitive theories, summarizing arguments from psychology, philosophy, and linguistics to converge on the point that human categories extend far beyond observable similarities.