In the era of fake news, expert knowledge is easily dismissed. There’s a danger of pseudoscience and nonsense replacing rational thinking. A core aim of science education is to teach scientific literacy: this should help to combat the rise of pseudoscience. But the question is, are we succeeding?

Creationism or believing that the Earth is flat or that gravity isn’t real are extreme positions often dismissed as crank views. More harmful are the rise of the anti-vaccination lobby and climate change denial. How, in the 21st century, can we have such anti-scientific thinking if science is a core school subject?

The problem is that, while we teach “science literacy” - ie, a lot of facts - we don’t necessarily teach “scientific literacy”. We give children skills, such as how to perform fair experiments or gather good data. But we’re not good at delivering an education about science. As well as knowing facts, pupils need to understand the nature of science.

The nature of science draws a distinction between theories and laws, and between observation and inference. It recognises that science involves creativity and imagination, that scientific knowledge is subjective or theory-laden. It acknowledges that science, as a human enterprise, is practised in the context of a larger culture. Most importantly, it recognises that scientific knowledge is never absolute or certain.

Overstating understanding

The current focus on a “knowledge-rich” curriculum may inadvertently lead to knowledge without requisite understanding. This leaves children open to the Dunning-Kruger effect, best described as learning something new and gaining a false confidence in your ability, leading to you overstating your understanding of what you’ve learned.

My research concentrates on why people believe strange things, and how understanding the nature of science can improve scientific literacy. Over the past 30 years, our curriculum has tried, with varying degrees of success, to deliver a form of the nature of science, previously called “how science works” and now “working scientifically”. But nowhere is it clearly articulated for teachers what is meant by the nature of science. Too often, teaching concentrates on the facts, processes and skills of science - that is, how to do investigations, take readings, collect data, and so on - rather than understanding the nature of science.

No matter how many scientific “facts” we teach children, they will never know enough to verify the claims of major research on things like climate change, genetically modified crops, fracking or most medical issues, including vaccination.

A second problem is that textbooks and specifications rarely produce clear, precise definitions of key scientific terms such as “theory”, “law” or “principle”. There is a misguided assumption that teachers have a common understanding of what these mean.

Finally, when we talk about “science”, people generally split this into three disciplines: biology, chemistry and physics. Real-world science is multidisciplinary and encompasses as wide a variation in approaches and disciplines as the differences between history and geography.

In 1869, biologist Thomas Henry Huxley said: “I do not mean that every schoolboy [sic] should be taught everything in science. That would be a very absurd thing to conceive, and a very mischievous thing to attempt.”

With the current focus on a knowledge-rich curriculum, there is a danger that this becomes a misguided clarion call for stuffing more facts into children’s heads. But how do we decide what science to teach? The original content of school exams was determined by what was thought essential for studying at university. Science degrees are now so diverse that this has become impossible. Current exam specifications contain far more than we deemed appropriate 30 or 40 years ago. We can’t keep on adding content.

A basic knowledge of the sciences is essential, but what that basic content should be is subject to debate. Should we teach overarching concepts and drill down to the “facts” or build up from the facts to construct the main concepts? What’s certain, in my view, is that it is of equal value to teach children how knowledge is generated from scientific reasoning.

Understanding deductive, inductive or abductive reasoning is crucial in distinguishing the characteristics of the different science disciplines. Not all science is “done” the same way. The methods used by a theoretical physicist bear little to no relation to those used by an environmental biologist. A physicist may start with a theory put in mathematical terms and then test that theory in a deductive way, moving from the specific to the general. A biologist will do almost the exact opposite, taking general observations to inductively build up to a specific theory.

Theoretical confusion

There’s a distinct lack of understanding of these ways of working by science teachers, who also misunderstand the mythical “scientific method”, seeing it as simply “how you do and report an experiment”.

Over a period of years, I’ve surveyed more than 180 science graduates entering initial teacher training. I asked them to provide simple definitions for terms such as theory, law, hypothesis and fact. This resulted in a very low “correct” response rate. Some provided popular or vernacular definitions - for example, thinking of a theory as a “guess” or “hunch”. Others defined a “law” as “rules to be followed in society”. Few could articulate a difference between “principle” and “law”.

Evolution suffers from a misunderstanding of what a theory is in science - the common mantra “it’s just a theory” is a creationist taunt that implies evolution isn’t “proven” or a “fact”. Creationists say, “If evolution were true, it would be a law.” Many of the surveyed graduates also incorrectly saw the move from theory to law as a form of hierarchy, indicating that theories became laws when they were “proven” (possibly passing through “principle” on the way).

Theories never become laws. Theories explain, laws describe. We must differentiate the scientific terms we use so that it’s clear if a word is being used in a specific way. I’d suggest using the prefix “scientific” with words such as theory, law, fact, principle and hypothesis.

We need a fundamental review of our science curriculum that will allow space for teachers to teach about the nature of science and the reasoning used by scientists. Core scientific knowledge is a must, but let’s not get so hung up on teaching the facts of science that we lose a sense of what science is all about.

James Williams is a lecturer in education at the University of Sussex. This article is an edited version of the 2018 Blackham Lecture for Humanists UK, which was delivered last week