Why are rocks pointy? Children's preference for teleological explanations of the natural world

Teleological explanations are based on the assumption that an object or behavior exists for a purpose. Two studies explored the tendency of adults and first-, second-, and fourth-grade elementary-school children to explain the properties of living and nonliving natural kinds in teleological terms. Consistent with the hypothesis that young children possess a promiscuous teleological tendency, Study 1 found that children were more likely than adults to broadly explain the properties of both living and nonliving natural kinds in teleological terms, although the kinds of functions that they endorsed varied with age. Study 2 was an attempt to reduce children's broad teleological bias by introducing a pretrial that described, in nonteleological terms, the physical process by which nonliving natural kinds form. In spite of this attempt, Study 2 replicated the effects of Study 1, with only fourth graders showing any shift in preference for teleological explanation.     

Purity matters more than harm in moral judgments of suicide: Response to Gray (2014)

Many people judge suicide to be immoral. We have found evidence that these moral judgments are primarily predicted by people’s belief that suicide taints the soul and by independent concerns about purity. This finding is inconsistent with accounts that define morality as fundamentally based upon harm considerations. In this commentary, we respond to a critique of our finding, and we provide further support for our original conclusions. Even when applying new exclusion criteria to our data, an examination of effect sizes demonstrates that concerns about purity robustly and meaningfully explain variance in moral judgments of suicide. While harm concerns sometimes predict moral judgments of suicide alongside purity concerns, they reliably explain a much smaller proportion of the variance than do purity concerns. Therefore, data from six studies continue to suggest that the relevance of harm concerns for moral judgments of suicide is substantially overshadowed by the contribution of purity concerns.     

State-Dependent Memory Effects Using Caffeine and Placebo Do Not Extend to Metamemory

The authors examined the impact of caffeine on human memory and predictions of memory (i.e., metamemory). On Day 1, 83 college students drank a sweetened beverage containing either caffeine (4 mg/kg body weight) or a placebo before they studied 40 pairs of words. While the participants studied, they predicted their future memory performance for each word pair. On Day 2, the participants again received caffeine or a placebo before the memory test. The participants who drank the same beverage on both days (either caffeine or a placebo) recalled more word pairs than did those who drank different beverages (caffeine on 1 day and a placebo on the other day). In contrast, memory predictions were more accurate when the beverages did not match on both days. These data provide evidence for state-dependent memory when caffeine is used, but not for state-dependent metamemory. People's memory and their predictions of memory can be influenced in different ways if they drink caffeine before they study or take a test.     

State-dependent memory effects using caffeine and placebo do not extend to metamemory

The authors examined the impact of caffeine on human memory and predictions of memory (i.e., metamemory). On Day 1, 83 college students drank a sweetened beverage containing either caffeine (4 mg/kg body weight) or a placebo before they studied 40 pairs of words. While the participants studied, they predicted their future memory performance for each word pair. On Day 2, the participants again received caffeine or a placebo before the memory test. The participants who drank the same beverage on both days (either caffeine or a placebo) recalled more word pairs than did those who drank different beverages (caffeine on 1 day and a placebo on the other day). In contrast, memory predictions were more accurate when the beverages did not match on both days. These data provide evidence for state-dependent memory when caffeine is used, but not for state-dependent metamemory. People's memory and their predictions of memory can be influenced in different ways if they drink caffeine before they study or take a test.     

The scope of teleological thinking in preschool children

These studies explore the scope of young children's teleological tendency to view entities as ‘designed for purposes'. One view (‘Selective Teleology') argues that teleology is an innate, basic mode of thinking that, throughout development, is selectively applied by children and adults to artifacts and biological properties. An alternative proposal (‘Promiscuous Teleology') argues that teleological reasoning derives from children's knowledge of intentionality and is not restricted to any particular category of phenomena until later in development. Two studies explored the predictions of these two hypotheses regarding the scope of children's functional intuitions. Using different methods, both studies found that, unlike adults, preschoolers tend to attribute functions to all kinds of objects – clocks, tigers, clouds and their parts. A third study then explored this finding further by examining whether the developmental effect was due to differences in children's and adults' concept of function. It found that both children and adults predominantly view an object's function as the activity it was designed to perform. Possible explanations for the developmental differences found in the first two studies, and implications for notions of a teleological stance are discussed.     

Young children's rapid learning about artifacts

Tool use is central to interdisciplinary debates about the evolution and distinctiveness of human intelligence, yet little is actually known about how human conceptions of artifacts develop. Results across these two studies show that even 2-year-olds approach artifacts in ways distinct from captive tool-using monkeys. Contrary to adult intuition, children do not treat all objects with appropriate properties as equally good means to an end. Instead, they use social information to rapidly form enduring artifact categories. After only one exposure to an artifact's functional use, children will construe the tool as 'for' that particular purpose and, furthermore, avoid using it for another feasible purpose. This teleo-functional tendency to categorize tools by intentional use represents a precursor to the design stance - the adult-like tendency to understand objects in terms of intended function - and provides an early foundation for apparently distinctive human abilities in efficient long-term tool use and design.     

Inferring design: evidence of a preference for teleological explanations in patients with Alzheimer's disease

Unlike educated adults, young children demonstrate a "promiscuous" tendency to explain objects and phenomena by reference to functions, endorsing what are called teleological explanations. This tendency becomes more selective as children acquire increasingly coherent beliefs about causal mechanisms, but it is unknown whether a widespread preference for teleology is ever truly outgrown. The study reported here investigated this question by examining explanatory judgments in patients with Alzheimer's disease (AD), whose dementia affects the rich causal beliefs adults typically consult in evaluating explanations. The results indicate that unlike healthy adults, AD patients systematically and promiscuously prefer teleological explanations, suggesting that an underlying tendency to construe the world in terms of functions persists throughout life. This finding has broad relevance not only to understanding conceptual impairments in AD, but also to theories of development, learning, and conceptual change. Moreover, this finding sheds light on the intuitive appeal of creationism.     

Reasoning about artifacts at 24 months: the developing teleo-functional stance

From the age of 2.5, children use social information to rapidly form enduring function-based artifact categories. The present study asked whether even younger children likewise constrain their use of objects according to teleo-functional beliefs that artifacts are "for" particular purposes, or whether they use objects as means to any desired end. Twenty-four-month-old toddlers learned about two novel tools that were physically equivalent but perceptually distinct; one tool was assigned implicit function information through a short demonstration. At test, toddlers returned to the demonstrated tool when asked to repeat the task, but, unlike older children, also used it for another task. Results imply that at 24 months, toddlers expect artifacts to have functions and proficiently use a model's intentional use to inform tool choices, suggesting cognition that differs from that of tool-using monkeys. However, their artifact representations are not yet specified enough to support exclusive patterns of tool use.     

Congruity influences memory and judgments of learning during survival processing

A recent line of research has suggested that memory systems evolved to encode fitness-relevant information more effectively than other types of information—a phenomenon known as the “survival processing effect” (Nairne, Thompson, & Pandeirada Journal of Experimental Psychology: Learning, Memory, and Cognition 33:263–273, 2007). However, the basis for the effect has been debated. In addition, it is unknown whether or not individuals will adjust their judgments of learning (JOLs) to reflect the survival processing effect. In three experiments, participants rated 16 words for their relevance to a survival scenario and another 16 words for their relevance to a bank robbery scenario. In Experiment 1A (with no JOLs), the survival processing effect emerged; in Experiment 1B (with JOLs), no survival processing effect emerged, but JOLs were higher in the survival condition. In both cases, these findings were confounded by higher relevance ratings in the survival condition. In Experiment 2, relevance was manipulated within each list, and the survival processing effect was eliminated. Instead, both recall and JOL magnitude were related to level of congruity between the words and type of processing. Together, these results provide further evidence for the role of congruity in the survival processing effect and JOLs.