Partial Mental Simulation Explains Fallacies in Physical Reasoning

People can reason intuitively, efficiently, and accurately about everyday physical events. Recent accounts suggest that people use mental simulation to make such intuitive physical judgments. But mental simulation models are computationally expensive; how is physical reasoning relatively accurate, while maintaining computational tractability? We suggest that people make use of partial simulation, mentally moving forward in time only parts of the world deemed relevant. We propose a novel partial simulation model, and test it on the physical conjunction fallacy, a recently observed phenomenon (Ludwin-Peery, Bramley, Davis, & Gureckis, 2020) that poses a challenge for full simulation models. We find an excellent fit between our model's predictions and human performance on a set of scenarios that build on and extend those used by Ludwin-Peery et al. (2020), quantitatively and qualitatively accounting for a deviation from optimal performance. Our results suggest more generally how we allocate cognitive resources to efficiently represent and simulate physical scenes.

Bringing physical reasoning into statistical practice in climate-change science

The treatment of uncertainty in climate-change science is dominated by the far-reaching influence of the ‘frequentist’ tradition in statistics, which interprets uncertainty in terms of sampling statistics and emphasizes p-values and statistical significance. This is the normative standard in the journals where most climate-change science is published. Yet a sampling distribution is not always meaningful (there is only one planet Earth). Moreover, scientific statements about climate change are hypotheses, and the frequentist tradition has no way of expressing the uncertainty of a hypothesis. As a result, in climate-change science, there is generally a disconnect between physical reasoning and statistical practice. This paper explores how the frequentist statistical methods used in climate-change science can be embedded within the more general framework of probability theory, which is based on very simple logical principles. In this way, the physical reasoning represented in scientific hypotheses, which underpins climate-change science, can be brought into statistical practice in a transparent and logically rigorous way. The principles are illustrated through three examples of controversial scientific topics: the alleged global warming hiatus, Arctic-midlatitude linkages, and extreme event attribution. These examples show how the principles can be applied, in order to develop better scientific practice.“La théorie des probabilités n’est que le bon sens reduit au calcul.” (Pierre-Simon Laplace, Essai Philosophiques sur les Probabilités, 1819).“It is sometimes considered a paradox that the answer depends not only on the observations but on the question; it should be a platitude.” (Harold Jeffreys, Theory of Probability, 1st edition, 1939).

Solutions of the Ortvay Rudolf International Competition in Physics: Exploding Refrigerator (2016/10 Problem)

The Ortvay Rudolf international competition was first organized in 1970. The focus is usually not on routine school-level problems but rather on problem-solving relying on physical reasoning and skills in recognizing the fundamental character and “heart” of the problem. Some problems lead the contestants to so-far unsolved, open questions, while some are accessible to first-year students. However, only for a relatively small number of problems do official solutions exist. The intention of this paper is to be the first in a series of published solutions discussing the competition problems. The problem treated below is a simple exercise about heat transfer in a thermodynamic system, which highlights the limitations and consequences of accepting seemingly intuitive approximations, and gives a didactical example of “explosive” dynamics. The calculation does not use mathematical techniques beyond those commonly expected of high school students.

Meta-strategy learning in physical problem-solving: the effect of embodied experience

'Embodied cognition' suggests that our experience in our bodies -- including our motor experiences -- shape our cognitive and perceptual capabilities broadly. Much work has studied how differences in the physical body (either natural or manipulated) can impact peoples' cognitive and perceptual capacities, but often these judgments relate directly to those body differences. Here we focus instead on how natural embodied experience affects what kinds of abstract physical problem-solving strategies people use in a virtual task. We compare how groups with different embodied experience -- children and adults with congenital limb differences versus those born with two hands -- perform on this task, and find that while there is no difference in overall accuracy or time to complete the task, the groups use different meta-strategies to come to solutions. Specifically, both children and adults born with limb differences take a longer time to think before acting, and as a result take fewer overall actions to reach solutions to physical reasoning problems. Conversely, the process of development affects the particular actions children use as they age regardless of how many hands they were born with, as well as their persistence with their current strategy. Taken together, our findings suggest that differences in embodied experience drive the acquisition of different meta-strategies for balancing acting with thinking, deciding what kinds of actions to try, and deciding how persistent to be with a current action plan.

The potential for effective reasoning guides children’s preference for small group discussion over crowdsourcing

Communication between social learners can make a group collectively “wiser” than any individual, but conformist tendencies can also distort collective judgment. We asked whether intuitions about when communication is likely to improve or distort collective judgment could allow social learners take advantage of the benefits of communication while minimizing the risks. In three experiments (n=360), 7- to 10-year old children and adults decided whether to refer a question to a small group for discussion or “crowdsource” independent judgments from individual advisors. For problems which could be conclusively solved through “demonstrable” analytic or physical reasoning, all ages preferred to consult the group, even compared to a crowd ten times as large — consistent with past research suggesting that groups regularly outperform even their best members for reasoning problems. In contrast, we observed a consistent developmental shift towards crowdsourcing independent judgments when reasoning by itself was insufficient to conclusively answer a question. Results suggest sophisticated intuitions about the nature of social influence and collective intelligence may guide our social learning strategies from early in development.

Associations of Prenatal Exposure to Phthalates with Measures of Cognition in 4.5-Month-Old Infants

The association of prenatal phthalate exposure with physical reasoning was assessed in 159 (78 female; 81 male) 4.5-month-old infants from a prospective cohort. Phthalate metabolites were quantified in urine from 16–18 gestational weeks and a pool of five urines from across pregnancy. Infants’ looking times to physically impossible and possible events were recorded via infrared eye-tracking. Infants that recognize that one of the events is impossible will look at that event longer. Associations of phthalate biomarkers with looking time differences (impossible–possible) were adjusted for maternal age, infant sex, and order of event presentation, and effect modification by infant sex was assessed. Each interquartile range (IQR) increase of monoethyl phthalate in the pooled sample was associated with females’ increased looking time (β = 1.0; 95%CI = 0.3, 1.7 s) to the impossible event. However, for males, an IQR increase in monoethyl phthalate at 16–18 weeks (β = −2.5; 95%CI = −4.4,−0.6 s), the sum of di(isononyl) phthalate metabolites in the pooled sample (β = −1.0; 95%CI = −1.8, −0.1 s), and the sum of all phthalate metabolites in both samples (β = −2.3; 95%CI = −4.4, −0.2 s) were associated with increased looking to the possible event, suggesting that higher prenatal phthalate exposure is associated with poorer physical reasoning in male infants.

Limits on Simulation Approaches in Intuitive Physics

A popular explanation of the human ability for physical reasoning is that it depends on a sophisticated ability to perform mental simulations. According to this perspective, physical reasoning problems are approached by repeatedly simulating relevant aspects of a scenario, with noise, and making judgments based on aggregation over these simulations. In this paper, we describe three core tenets of simulation approaches, theoretical commitments that must be present in order for a simulation approach to be viable. The identification of these tenets threatens the plausibility of simulation as a theory of physical reasoning, because they appear to be incompatible with what we know about cognition more generally. To investigate this apparent contradiction, we describe three experiments involving simple physical judgments and predictions, and argue their results challenge these core predictions of theories of mental simulation.