• The history of science is full of examples of discoveries and inventions that would never have been born if the minds of scientists did not roam the world of the imagination
• The role of the imagination in the process of scientific discovery is best demonstrated by the so-called thought experiments
• The idea is very simple: instead of conducting an experiment in the lab empirically, the scientist sits down comfortably in the chair so that his imagination and intuition can work.
• Can a thought experiment – independent of other purely empirical activities – reveal to us a fragment of the truth about the universe and our reality?
• More such stories can be found on the main page of Onet.pl

Primary imagination

Should a scientist have imagination? Can it afford to float in a fantasy world, away from the predictable, rational laboratory? The history of science is full of examples of discoveries and inventions that would never have been born if the minds of scientists hadn’t floated in the world of the imagination. We shouldn’t be surprised either! Our animal ancestors – as many behavioral observations have repeatedly shown – also have what we might call “imaginations.”

For example, chimpanzees can pretend that an object is something different than it actually is – there are known cases of animals caring for an inanimate object, such as a newborn baby. Bonobos can play such staged “games” before their eyes, pretending, for example, to discover food previously hidden in strategic places. Rats undergoing training to memorize the layout of the maze appear to mimic its course in their brains even during sleep: Neurological studies show that rats show similar patterns of brain activity during sleep as when learning a maze while they are awake.

Does this mean that the imagination is an evolutionary invention, a tool that perhaps gave our ancestors an advantage in the selection race – so that it survived as a form of brain activity, and was developed by us humans to an impressive size? If this is the case, it should come as no surprise that imagination plays a large role in science, which is based on creativity like almost no other area of ​​our activity. Science historians, speaking of the researcher’s imagination, often cite the history of deciphering the structure of benzene. August Kekulé is said to have discovered the structure of this organic compound under the influence of “wake sleep”, in which a snake grabbing its tail led it to the ring structure of the benzene molecule. This is just one example of how a flash of genius can intertwine with a rich fantasy, resulting in a “eureka moment”. The role of the imagination in the process of scientific discovery is best demonstrated by so-called thought experiments.

Prediction Tests

The idea is very simple: instead of conducting an experiment in the laboratory empirically, the scientist sits comfortably in the chair and lets his imagination and intuition work. This is often the only way to “test” some predictions. Albert Einstein found the foundations of the theory of relativity, among other things, thanks to thought experiments in which he considered, for example, racing with a light beam. Of course, not all thought experiments need to be about such surreal, impossible situations. One of the best examples is perhaps Galileo’s most beautiful thought experiment, who considered the fall of bodies of different masses under the influence of gravity.

In this experiment, Galileo was confronted with the predictions of another researcher and philosopher from ancient Greece – Aristotle. Aristotle believed that bodies of different weights should fall at different speeds. The lead ball must hit the ground faster than a wood ball falling at the same time and from the same height. Galileo adopted a superb tactic of dealing with this problem purely mentally. Suppose, Galileo argued, that what Aristotle really wanted was: a wooden ball should fall more slowly than a lead ball. Now imagine that we connect two such dropballs with a rigid pole. During a free fall, the lighter ball has to slow down the fall of the heavy ball – after all, it tends to fall more slowly. At the same time, however, combining two spheres creates a new object with a total mass greater than the mass of two separate spheres: according to Aristotle, such an object should fall faster than each of the spheres individually! We come to a contradiction that Galileo’s experiment solved in a wonderfully simple way: bodies fall freely at the same rate, regardless of their mass. A nice and simple conclusion – and also easy to confirm empirically (which, incidentally, was done many times in Galileo’s time and later).

thought experiments

Was Galileo’s thought experiment, fully realized in the imaginary world of his imagination, science in the full sense of the word? Has he finally verified a hypothesis – and can his conclusions be considered equivalent to the conclusions of a physical experiment conducted in the empiricist’s studio? By asking this question, we are actually touching on a more fundamental problem. Can a thought experiment – independent of other purely empirical activities – reveal to us a fragment of the truth about the universe and our reality? It is possible – as many philosophers and psychologists agree – that a thought experiment is just a kind of argument, some form of insight into the vastness of our personal experience that we have a priori about the world around us, based on our previous sensual experiences and perceptions. In such an interpretation, thought experiments would merely be clever constructs that support thinking, but far from actually treating a hypothesis through proper experience.

Only – is it certain that such excursions of the imagination are completely robbed of their importance and role in the process of scientific knowledge? Almost certainly not! After all, thought experiments, even if they are just explorations of our established experiences, are extremely fast, intuitive tools that unconsciously discover connections between facts. Careful and methodical planning of actual experiences often leaves us no room for such intuitive spontaneity. It remains to accept that the imagination is as important a part of the practice of science as observations and experiments carefully noted in laboratory notebooks. Without it, we would probably wait much longer for many discoveries. The theory of relativity, the laws of quantum mechanics or even the structure of DNA (the discoverers Watson and Crick have repeatedly emphasized the role of spatial imagination in the ultimate decoding of the double helix structure) – all these discoveries would not exist without using from the power of the human imagination to scientific inquiry.

The article is published in collaboration with Popularization Gate, Knowledge Trasfer Gate and Social Engagement Gate as part of Jagiellonian University’s Strategic Program Excellence Initiative