Kids do not need school to learn about cause and effect; they believe in causal laws well before kindergarten.
When cognitive scientists Laura E. Schulz of the Massachusetts Institute of Technology and Jessica Sommerville of the University of Washington tested preschoolers, they discovered that the kids were thoroughgoing “causal determinists.” The children assumed that everything happens for a reason. Schulz and Sommerville showed the kids toy lights and switches that either worked all the time or only some of the time. The children then were asked to make them light up — or to prevent them from lighting. “The children consistently behaved as if the lights and switches operated sensibly — that effects happened for reasons,” Schulz says. When the contraptions were rigged to shine only occasionally, “children looked for hidden switches that might have blocked the toys, rather than accepting that the toys might operate at random.”
The children’s fundamental assumptions both “enabled” and “constrained” their search for causes for the lights’ behavior, Schulz adds. For example, children proposed ideas about hidden switches to explain why a toy might not always work. The insights are important, Schulz explains, because children’s theoretical frameworks affect their learning processes. Sommerville says that knowing that children hunt for and observe causes can help teachers find more effective ways to transfer knowledge.
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In future research Schulz wants to look at how children deal with “psychological indeterminacy” — when people do not always return a smile, for example. “They may use a different set of assumptions when they analyze human behavior,” she says. —Jonathan Beard
FLASH
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