“Jesus answered,…”for this I have come into the world, to bear witness to the truth”
…Pilate said to him, “What is truth?” (John 18:37,38)
Philosophers have argued long and hard about Truth. Is there such a thing as a true statement? What do we mean if we say that something is true? In everyday life, “true” is contrasted with “false”. If I say that my new car is red, then we can check – is it red or is it, in fact orange? (Philosophers will, of course, ask what we mean by “red”…)
In science, notions of truth and falsity tend to be uncomplicated. When I formulate a hypothesis, and design an experiment, I’m aware that Nature will dispense its verdict: the results will either be consistent with the predictions of my hypothesis, or they will not, in which case it will be falsified.
Karl Popper provided the most influential model for describing scientific progress. According to Popper, science is a process of conjecture and refutation: we formulate hypotheses (make conjectures) and we test their predictions. If a hypothesis fails the test, it is falsified; if it passes the test it is corroborated.
For Popper, it was a characteristic of scientific hypotheses that they were always subject to possible falsification: a hypothesis should always specify the conditions under which it would be considered to be falsified. Thus, corroboration does not mean “true”, still less “proven”. Even such well-established hypotheses as the laws of thermodynamics, which have been subject to millions of tests without any known failures, are not “proved” according to Popper.
Importantly, however, corroboration increases the degree of confidence that we have in a hypothesis. Newton’s laws are very highly corroborated and we happily board aircraft despite the fact that the principles used in their design are fallible.
But if theories are not true, where does all this confidence spring from? Popper argues that science is fundamentally grounded in realism – the idea that there is an external reality that exists independently of our perception or understanding of it. As scientific knowledge advances, hypotheses are replaced by better hypotheses that explain more and that provide more accurate predictions; thus knowledge evolves.
Popper was a proponent of the correspondence theory of truth: truth in a theory consists in correspondence between the objects in the theory and objects in the natural world. Thus, scientific progress through the process of conjecture and refutation leads to theories that correspond ever more closely to the structures of the real, external world: they become more truth-like, even though we can never say that they are true.
Popper went further: he argued that while science, with its experimental method, allowed us to test hypotheses in a particularly efficient way, the essential methodology could be extended to other areas of human discourse. He propounded a philosophy that he called “critical rationalism”, based on the idea of “mutual control through rational criticism”. Once we accept the tenet that there is an external reality, and that our hypotheses can approach greater verisimilitude through an evolutionary process of conjecture and refutation, then it no longer remains acceptable to merely believe whatever we want.
In my career as a scientist I have encountered very few (if any!) scientists who did not, consciously or unconsciously, adhere to some form of the correspondence theory. Realism is an unavoidable consequence of doing experimental science: to persist in adhering to a falsified hypothesis in the sciences is not heroic, but ridiculous.
Here we arrive at one of the great cultural clashes of modern times: in stark contrast, post-modern theory regards the idea of truth as correspondence to an objective reality as a totalitarian hangover from enlightenment rationalism. Our perceptions of the world are contingent on our perspective as observers; to offer external criticism of another’s understanding is to deny the validity of their perspective and experience.
Although there has been widespread academic criticism of post-modern thinking, it has achieved a dominant role in shaping public discourse and it has seeped deep into popular culture. When Oprah Winfrey invited Meghan and Harry to “share your truth” she asserted implicitly that truth is not a unique entity defined by correspondence to an objective external reality, but something particular to each individual. Did somebody in the Royal Family behave in a racist way? This was the most incendiary implication in the broadcast. Surely this could be established by consideration of evidence? Richard Dimbleby, the respected journalist, said he was astonished that former colleagues at the BBC appeared not even to want to ask questions about what actually took place. In the post-modern world, personal truth is granted an unassailable status even if it appears to clash with reality.
The concept of reality itself is undermined by the post-modern view of truth. Apparently without trace of irony, Kellyanne Conway offered “alternative facts” as evidence that what was false was true. Mutual control through rational criticism becomes impossible when the evidence can be created ex nihilo to meet the hypothesis.
The explosion of social media has provided the perfect expression for this post-modern approach to truth. Soundbites articulating reactions and emotions, propounding personal truths free of any accountability, supported by powerful algorithms that create echo chambers which offer affirmation, not criticism, have provided the Petri dish in which falsehoods can appear, be nurtured and eventually impact the real world.
After Joe Biden became president, the US Covid-19 vaccination programme proceeded at great pace. But subsequently, it slowed, more suddenly than had been hoped, because the United States has incubated some of the most egregious falsehoods of the pandemic. In their transition from virtual echo chambers to the public imagination they have persuaded millions of Americans to take actions that harm themselves and their fellow citizens. Myths about Covid abound. Even as mass graves were being dug in New York, many were still saying “its just like the seasonal flu”. Jair Bolsonaro, perhaps the most malignant and amoral of all the populist demagogues of recent years maintained this ludicrous falsehood throughout a pandemic that saw a terrifying death rate among his fellow citizens.
Some people resist vaccination because of twisted political principles: it is an expression of their freedom to endanger themselves and their fellow citizens. One might argue that fascism can be rational even if it appears to be morally bankrupt. But most vaccine hesitancy comes from an acceptance of falsehoods that appear to survive untroubled by serious criticism.
This postmodern approach to truth – based on alternative facts and personal truths – has led us into a dangerous twilight zone. And yet the greatest of liars perhaps know and fear – deep down – that there is in fact an objective reality. Trump’s election rallies spread Covid with gay abandon, he humiliated and undermined his scientific advisors, but quietly, under the radar, everybody who attended events in close contact with the president was tested for Covid. His close social interactions were stage-managed. When, eventually, he succumbed to Covid – as he inevitably would – no expense was spared as the very best medical resources were directed to his care. One would imagine that humility would follow, a recognition that the virus is real, but no such thing; instead, hubris and lies. And demonstrating the power of the lie, millions of Americans, despite the abundant deaths, their former president’s fallibility and the evidence for all to see, refused the vaccine.
Covid-19 is a small challenge compared to climate change. The evidence that climate change is happening is abundant: glaciers are melting, submarines can travel under the North Pole, and there are fast increasing incidences of extreme weather. If the machinery of social media and vested interests can wreak such havoc with the truth about the pandemic, what hope have we of dealing with this much bigger and more pressing challenge? How do we get past “your truth” towards a notion of “the truth”? We must never say that we have “the truth” but we can say with confidence that examination of evidence and rational criticism are the only sure ways to approach it.