No Courage, No Glory: Underestimating the Benefits of Providing Children with Mechanical Details
College-level science and engineering courses systematically simplify causal mechanisms, using idealizations such as frictionless surfaces, ideal gases, and perfectly inelastic interactions. Educators often extend these simplifying practices to children by completely eliminating mechanistic details in favor of isolated facts, high-level functions, methodology, and the nature of science.1,2,3. After all, mechanical details seem far beyond the reach of children, given that most adults cannot recognize, let alone provide, simplified explanations of how everyday objects work, despite their trust. in the contrary.4.5. For example, regular adult bicycle users in the UK seemed to know surprisingly little about how bicycles actually work, often endorsing designs where the chain spun around both the front and rear wheels.6. Yet the omission of discussions of the “guts” of how things work contradicts children’s ability to reason abstractly about causal systems as well as their early information-seeking behaviors.7.
Even infants selectively explore to learn more about the causal structure of their environment8.9. More generally, young children are selectively interested in cause and effect patternsten as well as properties that allow useful interventions on the systems11.12. Children’s preferences for finding information also guide their use of language. Children as young as three repeatedly ask for details of cause and effect through “why” and “how” questions13,14,15,16, behaviors that seem to be motivated in part by a mechanistic desire for information17. Likewise, children’s own explanations tend to focus on causal relationships and may improve their memory for causal information.18.19.20. Taken together, these results suggest that, from an early age, children actively seek causal information and are sensitive to the causal properties and potentials of objects.
Children’s interest in causal information not only enriches their own knowledge, but also influences how they reason about knowledge in other minds. Children as young as six see those with mechanistic knowledge as having broader, deeper and more generalizable knowledge21.22. Although the representations underlying such epistemic inferences are currently unclear, how children generalize mechanistic knowledge selectively across domains, but not between them (e.g. knowing how a clock works involves knowledge machines but not flowers) suggests that they are able to represent causality. properties shared between related types.
Children themselves reason mechanically from the first years of primary school23. Exposure to mechanisms could contribute to the formation of such representations, even if the mechanisms themselves are forgotten. For example, young children acquire a “meta-knowledge” of the relative causal complexity of biological devices and systems, despite an almost complete ignorance of how these systems actually work.24. Beyond the complexity, children also seem to acquire other types of insights into the broad causal patterns implicit in mechanistic descriptions. Here, we ask whether children acquire three informal hunches about internal combustion engines through exposure to mechanical details: transient but necessary containment of the fluid, synchronized operation of parts, and decentralized control of parts. In addition to ignoring concrete details, these types of mechanistic representations often persist in memory for longer.25,26,27. Ironically, presenting richly detailed causal mechanisms could foster learning of higher-level causal models that linger in memory, while the very details from which they were extracted degrade.
Recent work has begun to examine the impact of causal education on children’s abstract knowledge. In one study, a group of eight and nine-year-old students learned a complex subject, atomic-molecular theory, over ten weeks.28. Instead of focusing only on what atoms and molecules are, an instructor taught children how and why certain materials, and by extension the atoms and molecules that make them, have certain properties. By the end of the weekly sessions, the children’s abstract understanding of atomic theory and their curiosity about scientific topics improved significantly. So, after a relatively short period of causal instruction in atomic theory, children as young as eight years old were able to explain patterns of the periodic table in terms of electron structures and could predict the binding sequences between new configurations of atoms and molecules. Most strikingly, the children’s knowledge persisted for at least a year without further education.
In another series of studies29, four- and five-year-olds attempted to turn on a fan by manipulating a simple circuit, while a parent or experimenter provided mechanical or non-mechanical answers to their questions. Children who received mechanical feedback were not only more likely to turn on the ventilator, but also to successfully complete a second task involving a new circuit. These results suggest that informal exposure to mechanistic information helps children to reason abstractly about the functioning of a circuit system and to generalize this knowledge to similar systems.
While these studies demonstrate the impact of mechanistic information on children’s abstract knowledge and reasoning ability, they involved extensive, child-centered dialogue that varied with each child. In real-life contexts, young children are often passive viewers of mechanistic information, unable to ask sequences of how and why questions or receive feedback from others. Moreover, previous work has neither attributed a particular set of causal abstractions to children nor systematically measured them. Can specific causal abstractions be measured in tightly controlled experimental settings without personalized interactions between teacher and student, thus ensuring that information is shared with all participants in a uniform manner? Moreover, can children even form such abstractions from brief exposure to mechanistic information?
We answered these questions by showing the kids a short video designed to teach college-level adults about a complex device: an internal combustion engine. The video shows over a hundred distinct parts and, in seven minutes, thousands of distinct causal relationships between those parts. Next, we measured children’s memory for the concrete information explicitly mentioned in the video as well as their understanding of the abstract causal patterns implicit (but not explicitly stated) in the video. We assessed the children’s causal abstractions by asking them to select which of the two individuals was a “real” car engine expert. Importantly, one person provided a statement that corresponded to an abstract aspect of how a car engine works (for example, when one part goes faster, all other parts must also go faster), while the other adopted a plausible alternative (for example, when some parts go faster, others have to slow down). Therefore, the success of children in this task depends on whether or not they represent a particular abstract causal property of car engines. We compared the performance between children who did not watch the video, those who watched the video and were immediately tested, and those who viewed the video but were tested a week later.
The ability to infer abstract models from rich mechanistic information and apply that knowledge one week later may seem highly implausible to children: it contrasts sharply with the science programs recommended for young children by even the most unreliable interpretations. more ambitious next-generation science standards.30. It also contradicts the intuitions of adults. To demonstrate this contradiction, we asked adults to estimate the earliest age at which a majority of children would understand a video on a variety of topics ranging from simple to complex.
We recruited 41 adults through Amazon Mechanical Turk who participated for a fee. None were excluded. A total of 22 video topics were chosen and covered a wide range of content, including videos explicitly aimed at young children (e.g. Teletubbies) and adults (e.g. Game of Thrones), see Figure 1 for a complete list of items. Participants were shown a series of articles and asked to rate ‘at what age a majority of children would understand a video on / episode of [topic]”On a scale of 0 to 18 years. Participants repeated this procedure for each item, in random order. Of the 22 items, adults rated a video on how a car engine works as requiring the oldest age to understand, over 12 (M = 12.32, SD = 3.57), overshadowing videos on other complex or adult-oriented topics such as the Industrial Revolution, Game of Thrones, and how a computer works.
However, the sustained interest of young children in the mechanism suggests that the pessimistic assessment of adults may be wrong, especially given the impressive ability of children to assess the knowledge of others based on their causal understanding.31. We therefore expected to find lasting cognitive benefits in presenting complex mechanical events to young children. We tested children aged 6 to 9. While children at this age may reason about those with mechanistic knowledge, they have received minimal formal education on mechanisms and themselves have little mechanistic knowledge.30. Therefore, in addition to being well below the age at which adults expect to be able to understand how a car engine works, the performance of children aged 6 to 9 in the present study is less likely to be affected. ” be influenced by the knowledge they already have. compared to older children and adults.
We predicted that children who watched the video would remember mechanical details, such as the names and movement of parts. We also expected their memory of these details to deteriorate over time. More importantly, we predicted that the children who watched the video would gain knowledge about the relevant abstract causal patterns compared to the child witnesses who did not watch the video, even though these patterns were never directly communicated to them. We further predicted that children would retain this abstract knowledge a week after watching the video.