The scientific method throughout history

EPFL Summer Series: How science works. Looking to the past can help us better understand the workings of science today. Jérôme Baudry, Professor at the College of Humanities at EPFL, explains how the procedures for proving and communicating scientific results have changed over time.
Allegorie op wetenschappen L'Academie des Sciences © Rijksmuseum / Wikimedia Commons

We often hear people talk about “the scientific method” as the ultimate guarantee of rigor in experimental research, but what exactly does it entail? Is there really a single method that applies to all fields of science? How have different scientific communities agreed upon common definitions of proof and knowledge in order to allow for cumulative learning? Jérôme Baudry, tenure-track assistant professor and head of the Laboratory for the History of Science and Technology, tells us more.

As a historian, how do you understand the scientific method?

As a historian, the first thing I can say is that, even though it seems like the term “the scientific method” has been around forever, it’s actually quite a recent thing. In his 2020 book The Scientific Method: An Evolution of Thinking from Darwin to Dewey, the American historian of science Henry M. Cowles talked about how the expression emerged around the start of the 20th century. In fact, rather than being coined by scientists, it was a slogan used by people who wanted to champion the authority of science. The term “scientific method” first gained currency in the United States and was used among people working in popular science, education, and scientific management, also known as Taylorism. People generally think of the scientific method as a strict list or sequence of rules and steps – such as observation, hypothesis, prediction, experiment, and confirmation – that you need to follow if you want to do science “the right way”. However, while that’s not completely wrong, just looking at it as a list is a real disservice to scientific activity!

So then how do we move beyond that simplistic view?

Well, first we need to be sure that we all have the same understanding of what the “scientific method” is. There’s one key distinction which I think is useful here, and that’s the distinction between the context of discovery and the context of justification, which was put forward by the German engineer and philosopher Hans Reichenbach in his 1938 book Experience and Prediction. The context of discovery describes how a scientist arrives at a given result. This requires a number of cognitive processes or tools, such as observation, hypothesis and experimentation, but it also encompasses interpretation, comparison, formalization, analogy, visualization, and so on. The context of justification, on the other hand, refers to how a scientist presents his or her discovery and communicates it to other scientists, as well as how, in the process of communication, others determine whether or not that result is valid.

How do scientific procedures change between the context of discovery and the context of justification?

In terms of the context of discovery, I don’t really think there’s one single method or a ready-made formula. Which scientific processes are relevant will vary depending on the discipline, the era, the group doing the work – it might be a single scientist, or a global network of hundreds or even thousands of scientists – and even individual personalities. We shouldn’t forget that, in the context of discovery, scientific research is about exploring and creating. The context of justification is a different matter. When a new or updated result is found by a scientist or team of scientists, how do you get the scientific community at large to acknowledge it as a discovery? This takes us into a realm of sociology rather than psychology. There are certain values and standards shared by scientists in terms of communicating and confirming discoveries, and these values are crystallized in institutions such as reviews, conferences, scientific societies, and so forth.

What do you see as the biggest turning points in the history of the scientific method?

One key moment during development of the scientific method was the development of experimental science in the 17th and 18th centuries. Particularly when you look at it through the lens of the context of justification, experimental science posed some major problems in terms of the validity, reproducibility, and confidence level of scientific results. When a branch of science deals with demonstrative knowledge, such as math for example, in order to know whether something is true, you just need to read a mathematical proof – although I realize I’ve made that sound simpler than it is! The problem with experimental sciences is that experiments have to take place in a certain place and under certain conditions, which means that perhaps only a handful of people would be able to follow them directly. They also often make use of specialist equipment and techniques, as well as specific know-how that can’t easily be passed on, making it difficult to reproduce them. Given all this, we have to ask ourselves how can we produce definitive facts and how can we be sure that results are credible?

What practices and institutions have scientists developed over the years to support experimental science?

There are a number of practices and institutions, but one example is the “literary technology” – to use the term coined by historian of science Steven Shapin – which relates to how experiments are written up. In order to secure the foothold of experimental science in the 17th century, scientists came up with a brand-new way of reporting on science, in order to create the illusion that the reader is participating in the experiment first-hand. The prolixity, the detailed descriptions, the use of images, and the removal of personal perspective – making it feel like nature herself was speaking – became part of the scientific communication that came into being during this period. Another example is the “social technology” which relates to the founding of scientific societies, such as the Royal Society, founded in London in 1660 and the Académie Royale des Sciences, founded in Paris in 1666. These institutions created an environment where experimental science could be practiced and discussed publicly, moving it from secretive, private laboratories to an assembly of scientific peers, and creating a genuine scientific community.

Based on history, how do you imagine scientific research changing in the future?

I’m a historian, not a prophet! Still, it is interesting to note that a lot of current controversies actually echo those of the past. For example, debates about integrity and scientific fraud, or arguments about the shortcomings of the peer review system have been around for a long time. Concerning these issues, I think that digital technology offers us some possibilities that haven’t yet been fully explored. From the pre-publication platform, to the current open access movement, to trials with open peer review, there are a number of routes available for making scientific research more efficient, more transparent, and more accessible. Things have started to change, but we need to move faster and go further!