We examined categorical effects in color appearance in two tasks, which in part differed in the extent to which color naming was explicitly required for the response. In one, we measured the effects of color differences on perceptual grouping for hues that spanned the blue-green boundary, to test whether chromatic differences across the boundary…

A Grey parrot ("Psittacus erithacus") had previously been taught to use English count words ("one" through "sih" [six]) to label sets of one to six individual items (Pepperberg, 1994). He had also been taught to use the same count words to label the Arabic numerals 1 through 6. Without training, he inferred the relationship between the Arabic…

Philosophers use hypothetical duplication scenarios to explore intuitions about personal identity. Here we examined 5- to 6-year-olds' intuitions about the physical properties and memories of a live hamster that is apparently duplicated by a machine. In Study 1, children thought that more of the original's physical properties than episodic…

How do people decide which claims should be considered mere beliefs and which count as knowledge? Although little is known about how people attribute knowledge to others, philosophical debate about the nature of knowledge may provide a starting point. Traditionally, a belief that is both true and justified was thought to constitute knowledge.…

The concept of innateness appears in systematic research within cognitive science, but it also appears in less systematic modes of thought that long predate the scientific study of the mind. The present studies therefore explore the relationship between the properly scientific uses of this concept and its role in ordinary folk understanding.…

Bayesian orthodoxy posits a tight relationship between conditional probability and updating. Namely, the probability of an event "A" after learning "B" should equal the conditional probability of "A" given "B" prior to learning "B". We examine whether ordinary judgment conforms to the orthodox view. In three experiments we found substantial…

Humans can rapidly extract object and category information from an image despite surprising limitations in detecting changes to the individual parts of that image. In this article we provide evidence that the construction of a perceptual whole, or Gestalt, reduces awareness of changes to the parts of this object. This result suggests that the…

While infants' ability to discriminate quantities has been extensively studied, showing that this competence is present even in neonates, the ability to compute ordinal relations between magnitudes has received much less attention. Here we show that the ability to represent ordinal information embedded in size-based sequences is apparent at 4…

Extending the well-established negativity bias in human cognition to truth judgments, it was recently shown that negatively framed statistical statements are more likely to be considered true than formally equivalent statements framed positively. However, the underlying processes responsible for this effect are insufficiently understood.…

The traditional cognitive developmental perspective on moral acquisition posits that children actively construct moral beliefs by assessing the negative impacts of antisocial behaviors. This account is not easily applied to actions that are considered immoral despite lacking consequences for others' welfare. We studied the moralization of…

Comparison is one of the most ubiquitous and versatile mechanisms in human information processing. Previous research demonstrates that one consequence of comparative thinking is increased judgmental efficiency: Comparison allows for quicker judgments without a loss in accuracy. We hypothesised that a second potential consequence of comparative…

In acquiring number words, children exhibit a qualitative leap in which they transition from understanding a few number words, to possessing a rich system of interrelated numerical concepts. We present a computational framework for understanding this inductive leap as the consequence of statistical inference over a sufficiently powerful…

The present study investigated how children learn that some verbs may appear in the figure-locative but not the ground-locative construction (e.g., "Lisa poured water into the cup"; "*Lisa poured the cup with water"), with some showing the opposite pattern (e.g., "*Bart filled water into the cup"; "Bart filled the cup with water"), and others…

Where are we? In three experiments, we explore preschoolers' and adults' intuitions about the location of the self using a novel method that asks when an object is closet to a person. Children and adults judge objects near a person's eyes to be closer to her than objects near other parts of her body. This holds even when considering an alien…

Recent evidence suggests that people are highly efficient at detecting conflicting outputs produced by competing intuitive and analytic reasoning processes. Specifically, De Neys and Glumicic (2008) demonstrated that participants reason longer about problems that are characterized by conflict (as opposed to agreement) between stereotypical…