Teachers operate on the assumption that students are “empty vessels” they can fill with new information. But many students begin classes with assumptions about the world that, although intuitive, are actually incorrect. For example, many students incorrectly believe that individuals can evolve or that all members of a species evolve together. Teachers assume that instruction and testing will make students understand that both of these assumptions are wrong and that only populations evolve. However, recent research suggests that simply providing students with factual information doesn’t make them drop their faulty assumptions. As it turns out, old misconceptions die hard.
In a recent paper published in the journal Cognition, Shtulman and Valcarcel asked what happens to our old, naive assumptions after we are given new, correct information. Do they disappear as teachers hope? Or do they continue to dog us long after we’ve learned the correct scientific explanation? To answer these questions, the researchers gave 150 college students 200 statements from 10 domains of knowledge (Astronomy, Evolution, Fractions, Mechanics, etc.). They asked the students to determine whether each statement is True or False. Within each domain, these statements fell into one of four categories:
- True at both a naive and scientific levels (“Biological species evolve”)
- False at both naive and scientific levels (“Inanimate objects evolve”)
- True at a naive level but false at a scientific one (“Individual organisms evolve”)
- False at a naive level but true at a scientific one (“Computer viruses evolve”)
They recorded the speed and accuracy of the students’ responses and then analyzed the results. What they found is both intuitive and surprising.
As you might expect, the students identified statements that were true/false at both naive and scientific levels (“consistent statements”) much faster and more accurately than statements that were true at one level but false at the other (“inconsistent statements”). This result suggests that college students still have trouble identifying statements that seem intuitive but are actually incorrect. (To be fair, the authors note that even Biology professors have this problem. A separate study found that biology professors were slower at identify plants rather than animals as alive — a statement that is naively false but obviously very true). Students exhibited this pattern across all domains of knowledge, suggesting that naive assumptions may hinder students across multiple subjects, although accuracy was lowest for Evolution (sigh). But despite the observation that students had trouble identifying inconsistent statements across all subjects, the researchers also found that the students had an easier time with subjects they learned earlier rather than later in life (for example, third-grade Fractions versus highschool Evolution).
In the end, the researchers concluded that “scientific knowledge serves to mask, rather than replace, one’s initial intuitions.” They hypothesize that students have a harder time separating fact from fiction in subjects like Evolution because their naive theories are deeply entrenched by the time the students receive accurate instruction. In this respect, the new, scientific knowledge students receive could represent a formidable challenge to their long-held — but wrong — intuitions. The researchers note, “Not only must [science educators] help students learn the correct, scientific theory at hand, but they must also help students unlearn their earlier, less accurate theories.”
The implications for teaching Evolution are real. Since we develop or accept intuitive theories about the world early — like the assumption that Biblical creation can explain Biological diversity — understanding and accepting scientific facts like Evolution becomes even harder if we wait until high school to teach it, when naive theories are already entrenched. The obvious solution is to present students with accurate, scientific information earlier while also challenging and re-analyzing their incorrect assumptions. Really, Genesis I says that God created man last? Well, what does phylogenetics say? Or, for that matter, what about Genesis II?