Frank C. Keil

A characteristic-to-defining shift in the development of word meaning

Many word meanings seem to have a mixture of two representational types, sometimes known as characteristic and defining features. It is proposed that meanings typically develop from representations in which characteristic features predominate to those in which defining features become more central. (The same shift can also be described without the assumption of featural decomposition of meaning.) A study with preschool and elementary school children confirmed this proposal by showing that childrens judgments of whether brief stories described valid instances of a concept shifted in a manner predicted by these hypotheses.

Acquisition of the hierarchy of tonal functions in music

The acquisition of the hierarchy of tonal stabilities in music is investigated in children of elementary school age. Listeners judge how good short tone sequences sound as melodies. The ratings show a pattern of increasing differentiation of the pitches in an octave range. The youngest listeners distinguish between scale and nonscale tones; older listeners distinguish between the tonic triad tones and other scale components. A group of adult listeners show octave equivalence and temporal asymmetries, with a preference for sequences ending on the more stable tones within the hierarchy. Pitch height effects do not interact with the age of the listener. These results are discussed in terms of the primacy of physical variables, novice-expert differences, and general cognitive principles governing the acquisition and development of internal representations of pitch relationships.

Two Dogmas of Conceptual Empiricism: Implications for Hybrid Models of the Structure of Knowledge.

Concepts seem to consist of both an associative component based on tabulations of feature typicality and similarity judgments and an explanatory component based on rules and causal principles. However, there is much controversy about how each component functions in concept acquisition and use. Here we consider two assumptions, or dogmas, that embody this controversy and underlie much of the current cognitive science research on concepts. Dogma 1: Novel information is first processed via similarity judgments and only later is influenced by explanatory components. Dogma 2: Children initially have only a similarity-based component for learning concepts; the explanatory component develops on the foundation of this earlier component. We present both empirical and theoretical arguments that these dogmas are unfounded, particularly with respect to real world concepts; we contend that the dogmas arise from a particular species of empiricism that inhibits progress in the study of conceptual structure; and finally, we advocate the retention of a hybrid model of the structure of knowledge despite our rejection of these dogmas.

On the development of biologically specific beliefs: the case of inheritance

5 experiments investigated childrens intuitions about genetic transmission of features. After parent animals possessing an abnormal feature were described, children were asked whether their baby would be born with that feature in abnormal or normal form. Features were either internal or external, inborn or acquired after birth, and had functional or nonfunctional consequences for the parents. Among preschoolers, features with functional consequences were considered inherited much more frequently than any other type, but only when the functional consequences were biological rather than social or psychological. Older children demonstrated more awareness of the inheritance of inborn traits. Overall, the results suggest young children have principled, specifically biological notions of inheritance.

An abstract to concrete shift in the development of biological thought: the insides story

For more than a century, theorists of cognitive development have embraced some form of the thesis that cognitive development proceeds from concrete to abstract knowledge. In contrast to this view, we suggest an abstract to concrete shift in the development of biological thought. In five studies we examine childrens expectations for what could be inside animals and machines and we find that children of all ages respond systematically, revealing abstract expectations for how the insides of animals and machines should differ. By 8 years, children seem to have more concrete expectations for the nature of insides, and are substantially more accurate than preschoolers. More broadly, we suspect that an abstract to concrete progression may capture important features of how knowledge develops in the realm of biological thought and in many other areas of understanding as well.

What Do Children Want to Know About Animals and Artifacts?: Domain-Specific Requests for Information

Childrens questions may reveal a great deal about the characteristics of objects they consider to be conceptually important. Thirty-two preschool children were given opportunities to ask questions about unfamiliar artifacts and animals. The children asked ambiguous questions such as “What is it?” about artifacts and animals alike. However, they were more likely to ask about the functions of artifacts, but about category membership, food choices, and typical locations of animals. They never asked questions about either artifacts or animals that would be considered inappropriate by adults. The results indicate that children hold different expectations about the types of information important for categorizing living and artifact kinds. Young children conceive of artifacts in terms of functions, but conceive of animals in terms of biologically appropriate characteristics. Such results speak to debates about the role of function in childrens biological reasoning and to accounts of childrens artifact concepts.

Folkscience: coarse interpretations of a complex reality

The rise of appeals to intuitive theories in many areas of cognitive science must cope with a powerful fact. People understand the workings of the world around them in far less detail than they think. This illusion of knowledge depth has been uncovered in a series of recent studies and is caused by several distinctive properties of explanatory understanding not found in other forms of knowledge. Other experimental work has shown that people do have skeletal frameworks of expectations that constrain richer ad hoc theory construction on the fly. These frameworks are supplemented by an ability to evaluate and rely on the division of cognitive labour in ones culture, an ability shown to be present even in young children.

Constraints on constraints : Surveying the epigenetic landscape

It is now relatively commonplace to advocate the need for some sorts of constraints on leornlng ond knowledge acquisition. The critical issues to cognitive science concern the sorts of constraints thot ore able to best model various phenomena of learning and development. Four types of constraints on learning ore proposed to be used as an interpretative fromework within which to: 1. Better understand the nature of current research: 2. Allow the exploration of alternotive models of learning related phenomena, and 3. See more clearly needs for further research. Superficially similar learning phenomena can be modeled by very different configurations of underlying constraints with strong implications for the sorts of representational states that are involved. Each of the five papers in this issue and Spelke) is considered in terms of the configuration of constraints ofter which each author intends to model their phenomeno and in terms of alternate configurations. The papers are construed as illustrating a diverse set of models of how constraints might guide learning. and while the evidence generally favors the configurations suggested by the outhors, in each case olternotive models ore possible and motivate quite specific future research questions. Mare broadly, it is suggested that asking detailed questions about the sorts of constraints types thot could potentially model complex cases of natural knowledge acquisition helps motivate fundamental questions about learning and the nature of knowledge and that the five papers in this issue are superb examples of how adopting this klnd of perspective has been fruitful research orientation. for helpful comments on early drafts of this paper and to all of the authors in this issue for reactions to my comments. Several of the papers in this issue have gone through a great deal of evolution over the course of when I wrote my initial commentary over two years ago. I have tried to keep pace with these changes as much as possible , but a little insight into that process may help readers understand why I sometimes go on about issues that now are only lightly mentioned in some of the current versions of these papers.

Prototypicality in a Linguistic Context: Effects on Sentence Structure

tences in recall, preference ratings, and natural dictionary definitions. The first experiment showed that sentences were systematically changed in retail to allow prototypical instances of categories to be mentioned before nonprototypical instances. In the second experiment, sentences in which the prototype preceded the nonprototype were judged more natural than sentences with the opposite order. Finally, an examination of dictionary definitions of categories found that prototypes tended to occur before nonprototypes. These results can be explained in terms of the sensitivity of sentence production processes to the lexical or conceptual accessibility of prototypes. Such processes appear to adjust serial positions

The Shadows and Shallows of Explanation

We introduce two notions–the shadows and the shallows of explanation–in opening up explanation to broader, interdisciplinary investigation. The “shadows of explanation” refer to past philosophical efforts to provide either a conceptual analysis of explanation or in some other way to pinpoint the essence of explanation. The “shallows of explanation” refer to the phenomenon of having surprisingly limited everyday, individual cognitive abilities when it comes to explanation. Explanations are ubiquitous, but they typically are not accompanied by the depth that we might, prima facie, expect. We explain the existence of the shadows and shallows of explanation in terms of there being a theoretical abyss between explanation and richer, theoretical structures that are often attributed to people. We offer an account of the shallows, in particular, both in terms of shorn-down, internal, mental machinery, and in terms of an enriched, public symbolic environment, relative to the currently dominant ways of thinking about cognition and the world.