The Conversation: Foundational scientific theory under attack in statehouses

By RYAN SUMMERS
Of the University of North Dakota

Scientific theory has had a rough time in America’s public schools.

Almost 100 years ago, John Scopes was convicted of violating a Tennessee law prohibiting teaching the theory of evolution. Although his conviction was overturned on a technicality in 1927, laws banning classes on Darwin’s theory stuck around for another 40 years — until being ruled unconstitutional by the Supreme Court in 1968.

Over the past few decades, conservative or religious groups objecting to the study of evolution in science classes have tried a different approach. Now, they argue, if the “scientific” theory of evolution is taught, other views, such as “intelligent design,” a stand-in for creationism, should also be taught.

The approach is not limited to evolution either. Legislatures across the country are proposing or passing laws that purport to encourage scientific discussion, but instead encourage students to treat established scientific theories as equivalent to ideas that lack scientific rigor.

In 2012, legislators in Tennessee — the same state where the Scopes trial took place nearly a century ago — approved a law obligating teachers to present the “scientific strengths and scientific weaknesses of existing scientific theories.” But what constituted a scientific “strength” or “weakness” was not defined.

Similar bills were introduced in North Dakota in 2019 and Oklahoma in 2023.

A new law in West Virginia allows teachers to discuss or answer “questions from students about scientific theories.” The bill’s author, state Sen. Amy Grady, said it is aimed at “encouraging students to think, encouraging students to ask questions and encouraging our teachers to be able to answer them.”

In my view, legislation dealing with the teaching of scientific theories is being used to influence what is taught in public schools, and is likely to face legal challenge.

More than 20 years ago, in Kitzmiller v. Dover, a federal court ruled that intelligent design was not scientifically grounded, as it lacks empirical evidence and testable hypotheses. Teaching it would thus violate the First Amendment’s prohibition against state support of religion.

As an educator — and as a scholar who studies the nature of science — I believe an understanding of scientific knowledge is critical.

Scientific theories have been thoroughly tested and are supported by evidence — often evidence pulled from different fields. For example, evidence supporting large-scale evolution comes from fossils, DNA analysis and comparing the anatomy of different organisms.

Scientific theories can change or even be discarded. But in the main, they have proven durable.

The history of science is full of stories about new evidence, reinterpretation of existing evidence and advances in technology spurring changes in the sciences. For instance, the discovery of the microscope in the 16th century literally changed how scientists saw the world.

Scientific theories have explanatory power about the natural world. The Earth’s gravity, for instance, can be explained through the theory of general relativity.

As summarized by astrophysicist and author Neil deGrasse Tyson: “A well-constructed theory should explain some of what is not understood and, more importantly, predict previously unknown phenomena that can be tested. A successful theory is one where experiments consistently confirm its predictions.”

Given these characteristics, the current crop of legislation governing how theories are introduced and taught in classrooms is concerning. Underpinning these laws is the assumption that accepted scientific theories are nothing more than conjecture.

For example, a 2023 bill from Montana prohibits science instruction on “subject matter that is not scientific fact.”

The bill devalues scientific theories as hunches or unproved assumptions. It undermines their inclusion, as established ideas, in the K-12 curriculum.

Atomic theory may be a theory, but it is fundamental to people’s understanding of matter and is a foundation of all the physical sciences.

Legislation that invites classroom exploration, debate or analysis of theories may mask other intentions. The sponsor of Senate Bill 140 in Oklahoma, for example, said he hoped the law would “expose the ‘theory’ aspect of evolution by allowing alternate views to be presented.”

Laws like the one passed in West Virginia go a step further. They open the door to discussions about alternatives to scientific theories, allowing unscientific notions to be introduced covertly.

Writing for Scientific American, Amanda Townley, executive director of the National Center for Science Education, expressed concern. She said such laws open the public classroom door to false beliefs, such as the Earth being flat or that crystals can heal.

In contrast to legislators who would allow any kind of theory to be taught in science class, experts such as Fouad Abd-El-Khalick, a leading international science education researcher, advocate students in K-12 be taught the characteristics of scientific theories in developmentally appropriate ways.

U.S. standards for teaching science, for instance, say that by the end of 12th grade, students should understand that a “scientific theory is a substantiated explanation of some aspect of the natural world, based on a body of facts that has been repeatedly confirmed through observation and experiment.”

Students should be encouraged to think critically and ask questions — like, “What is the evidence that supports this theory?” or “How was this theory tested?” — with the caveat that any theories in question should have already attained the status of “scientific theory” before being admitted into the curriculum.

Education scholars say K-12 education must provide students a “functional level of scientific literacy,” enabling them to understand and make decisions about issues related to science in everyday life, from vaccination to baking cakes. Part of attaining this literacy is understanding and trusting knowledge produced by science, such as facts, laws — and scientific theories.

From The Conversation, an online repository of lay versions of academic research findings found at theconversation.com/us. Used with permission.