As we shall discuss at the conference, doubt is a many-faceted aspect of science. To get a sense of the importance of doubt within the manifold of science, one would have to explore many disciplines, from metaphysics to logic to sociology to politics.

Special thanks are therefore due to MSc Science Communication alumnus Philip Howard, who has compiled for us a selection of thoughts on doubt and science. Quite rightly, considering his Imperial degree, Philip here is particularly concerned with the question of how doubt can best be handled in relation to the communication of science in public arenas.

Doubt is a fundamental element of science

• Doubt is an essential part of the process of science. In the philosophy of science, from Sir Francis Bacon to Goethe to Sir Karl Popper, doubt in one’s hypotheses structures investigations, with their possible falsification perhaps just the next experiment away. For Popper, the route to good science is self-criticism.
• It is a matter of metaphysics that science – because of its empirical grounding – cannot reach certain knowledge. The physicist Richard Feynman, in his 1955 ‘The Value of Science’ Caltech lecture, said ‘When a scientist doesn’t know the answer to a problem, he is ignorant. When he has a hunch as to what the result is, he is uncertain. And when he is pretty darn sure of what the result is going to be, he is still in some doubt. We have found it of paramount importance that in order to progress we must recognize our ignorance and leave room for doubt. Scientific knowledge is a body of statements of varying degrees of certainty – some most unsure, some nearly sure, but none absolutely certain.’

Doubt is an engine of creativity

• Jennifer Michael Hecht in her 2004 ‘Doubt: a history’ celebrates doubt, in an evolving religious context, as an engine of creativity and an alternative to the political and intellectual dangers of certainty. Her book is long, but highly recommended as an example of ‘synthetic’ non-fiction writing.
• Why in science might we want to ‘protect’ doubt, and cherish it as a stimulus to thought? Johann Wolfgang von Goethe said ‘there is no permanence in doubt; it incites the mind to closer inquiry and experiment, from which, if rightly managed, certainty proceeds, and in this alone can man find thorough satisfaction’. Goethe suggests then that it is the ‘unsettledness’ of doubt, the way it needles you (‘incites the mind’), that is creative.
• Doubt ensures constructive dialogues between researchers and research groups. The clarity of settled knowledge emerges from the fog of competing hypotheses such that existing theories, and their inherent uncertainties, are replaced by new theories albeit with their own unknowns and doubts. Are we proud of a conclusion, if it was not accompanied by new questions and new doubts.
• By the end of the Victorian era some thought physics to be complete. But Lord Kelvin’s famous ‘two clouds’ lecture, given at the Royal Institution in 1900, highlighted two problems of classical physics. These doubts were resolved by the new quantum and relativistic physics of Planck and Einstein.
• Doubt is contemplative, but it also is practical. By unsettling us, it ensures that the complacencies of the great and the good can be challenged. Rutherford’s reference in 1933 to the industrial scale production of atomic energy as ‘Moonshine’ drove a doubting Leo Szilard to register a patent in 1934 for a viable chain reaction. Another example: Antoine Lavoisier, the father of modern chemistry, maintained that muriatic acid must contain oxygen. It took a young Humphry Davy, in 1810, to take the bold step to doubt the great man, and prove that muriatic acid, now called hydrochloric acid, contained no oxygen.

Doubt is more than just error bars, and eludes quantification

• The communication of science to wider groups of people challenges how doubt is presented.
• Emile Roux, an associate of Louis Pasteur and renowned scientist in his own right, said ‘Science appears calm and triumphant when it is completed; but science in the process of being done is only contradiction and torment, hope and disappointment.’
• Covid showed to the public science in the moment and how doubt is part of ‘science in the process’. Error bars were not enough to express the uncertainties and doubts in the science and could hardly calm the multiple social and political forces that interacted with scientifically-based predictions.
• In contrast, and as a taster of ‘Science Communication Studies’, see Brian Wynne’s paper on Cumbrian Hill farmers after the Chernobyl accident led to high levels of radioactive material in sheep.  The difficulty scientists had in acknowledging their own doubt and uncertainties, as they tried to undertand a situation far different from laboratory work and simple modesl led to them losing the trust of the hill farmers.
• We scientists, rather prone to suggesting that the public don’t understand that science is uncertain, might on second thoughts admit that most people are used to handling uncertainty and doubt as a fact of life. Might ‘the general public’ be more at ease with scientific doubt than scientists imagine ?

Reasonable versus Unreasonable Doubt

• Henri Poincaré, the great French physicist and mathematician, said ‘To doubt everything or to believe everything are two equally convenient solutions; both dispense with the necessity of reflection.’ And this is a basis for a thought-provoking article by David Allison, Gregory Pavela and Ivan Oransky.
• How can we prevent the ‘illegitimate co-option of doubt’ being used to undermine good science. According to Allison, Pavela and Oransky these are the occasions when ‘doubt is [used to create] disingenuous expressions of skepticism, motivated by financial or other nonscientific interests, which are allowed to pervert scientific interests.’
• But, on the other hand, we need to be careful as ‘The same tools used to discredit disingenuous expressions of doubt can be used against those who express well-supported doubt. Those with particular political views may declare some doubt to be unreasonable, even if it is actually quite reasonable.’
• In presenting climate change science how should we communicate the uncertainty in climate science without that doubt undermining the ‘beyond reasonable doubt’ science.

The ‘stupid’ do not doubt

• Bertrand Russell said, ‘The fundamental cause of the trouble is that in the modern world the stupid are cocksure while the intelligent are full of doubt.’
• How should we present science, the implications of science and our doubts and uncertainties, without undermining the legitimate authority of the science itself, and our own long-held expertise?
• In pushing back on those who try to exploit a scientific doubt to challenge the beyond reasonable doubt science, there is a danger. We need to avoid, as described by Allison, Pavela and Oransky, using counterproductive rhetoric to describe doubters as ‘“deniers,” “shills,” “fringe” persons, and the like”.
• ‘There truly are people—some of them in positions of authority—who are promoting disingenuous and unreasonable expressions of doubt. However, if we slip and rely on non-scientific rhetorical devices to argue against them, then we invite others to use these rhetorical devices to dismiss cases in which scientific doubt is reasonable and even essential.
• Are Allison et al right, when they say at the end of their article, ‘As scientists and scholars, we need to rise above [politics and rhetoric], stick to the science, and never give up the virtue of doubt’.

When dogma trumps doubt

• The consequences of people who are convinced they are right, with no doubt as to the ‘truth’ of their absolute knowledge, can have varied and profound consequences, especially when scientific dogma allies itself with vested interests and political dogma.
• Sometimes, scientists put doubt aside. Didier Raoult, a physician and a microbiologist, gained global fame for promoting hydroxychloroquine as a treatment for Covid-19 despite no evidence for its effectiveness and the subsequent opposition from experts around the world. On the other hand Charles Darwin, no stranger to doubt, was exceptionally stubborn on behalf of his theory of natural selection, and his belief that modern humans are a single species.
• A brilliant example of science communication, on the theme of dogma trumping doubt, comes in the episode ‘Knowledge or Certainty’ of Jacob Bronowski’s acclaimed 1973 Ascent of Man TV series. In it he says, ‘Science is a very human form of knowledge’ and scientists must always believe that they are ‘fallible and that they ‘may be mistaken’. The episode ends with Bronowski standing in a boggy pond outside Auschwitz. To Bronowksi, the consequences of a lack of doubt and the dominance of dogma and ignorance were all too plain to see and feel in the mud formed by the ashes of four million people. It is a theme echoed by the historian Sir Isiah Berlin, who saw, on occasion, a continuum between the simplifications of the Enlightenment, and totalitarianism.

‘I’m sorry, Dave, I’m afraid I can’t do that.’

• HAL 9000 in Space Odyssey 2001 also went on to say – ‘No 9000 computer has ever made a mistake or distorted information. We are all, by any practical definition of the words, fool-proof and incapable of error.’
• Could AI systems express doubt and, if so, could they then be more useful or more dangerous?
• Although much is written on AI and uncertainty there is very little on whether AI can ‘self-doubt’? Uncertainty in AI is about how AI deals with uncertain inputs or how humans assess the certainty of the output.
• There seems to be very little researched or written on whether AI systems can express doubt about their own output. If AI cannot doubt then does it become, as for Russell’s ‘cocksure’, stupid?
• Psychologist Steve Fleming at UCL argues that the ability to doubt separates humans from AI. The ‘metacognition’ of humans allows us to ‘think about our own thinking’ and ‘recognise when we might be wrong’.

Compiled by Philip Howard 26 August 2023 | Editor: Stephen Webster 

Read A thesaurus of doubt in full