Lance Rips

If people believe that one activity is a kind of another, they also tend to believe that the second activity is a part of the first. For example, they assert that deciding is a kind of thinking and that thinking is a part of deciding. C. Fellbaum and G. A. Miller's (see record 1991-03356-001) explanation for this phenomenon is based on the idea that people interpret part of in the domain of verbs as a type of logical entailment. Their explanation, however, suffers from at least 2 deficiencies. First, it fails to account for parallel effects with nouns (e.g., a contest is a kind of an activity, and an activity is a part of a contest). Second, it contains a flaw that incorrectly predicts many activities to be parts of each other (e.g., coming is part of going and going part of coming). However, a hypothesis L. J. Rips and F. G. Conrad (see record 1989-24843-001) originally proposed for the kind–part reciprocal effect avoids both of these difficulties.

A central aspect of people's beliefs about the mind is that mental activities—for example, thinking, reasoning, and problem solving—are interrelated, with some activities being kinds or parts of others. In common-sense psychology, reasoning is a kind of thinking and reasoning is part of problem solving. People's conceptions of these mental kinds and parts can furnish clues to the ordinary meaning of these terms and to the differences between folk and scientific psychology. In this article, we use a new technique for deriving partial orders to analyze subjects' decisions about whether one mental activity is a kind or part of another. The resulting taxonomies and partonomies differ from those of common object categories in exhibiting a converse relation in this domain: One mental activity is a part of another if the second is a kind of the first. The derived taxonomies and partonomies also allow us to predict results from further experiments that examine subjects' memory for these activities, their ratings of the activities' importance, and their judgments about whether there could be "possible minds" that possess some of the activities but not others.

First, we describe a psychological experiment in which the participants were asked to determine whether sentences of first-order logic were true or false in finite graphs. Second, we define two proof systems for reasoning about truth and falsity in first-order logic. These proof systems feature explicit models of cognitive resources such as declarative memory, procedural memory, working memory, and sensory memory. Third, we describe a computer program that is used to find the smallest proofs in the aforementioned proof systems when capacity limits are put on the cognitive resources. Finally, we investigate the correlation between a number of mathematical complexity measures defined on graphs and sentences and some psychological complexity measures that were recorded in the experiment