Truth is neither Absolute nor Timeless. But the Pursuit of Truth remains at the Heart of the Scientific Endeavour.
“…the Strength of the Thread does not Reside in the Fact that some one Fibre runs Through its whole Length, but in the Overlapping of many Fibres” Ludwig Wittgenstein
Think of the number of Scenarios in which Truth matters in Science. We care to know whether increased CO2 emission levels cause Climate change, and how fast. We care to know whether smoking tobacco increases the risk of lung cancer. We care to know whether poor Diet exposes Children to the Risk of developing Obesity, or whether forecasts of economic Growth are correct. Truth in Science is not Esoteric Dilly-Dallying. It shapes Climate Science, Medicine, Public Health, the economy and many other Worldly Endeavours.
That Truth Matters to Science is hardly News. For a long time, people have looked to Science for Truths about the World.
The Scientific Revolution was nothing if not the triumph of Galileo’s scientific Truth – hard-won Through his telescopic Observations, over Centuries of Dogma about the Geocentric System. With its System of Epicycles and deferents, Ptolemaic Astronomy was at once Sophisticated and False. It served to, at best, ‘Save the Appearances’ about how Planets seemed to move in the Sky. It did not tell the Truth about Planetary Motion until the discovery of the Copernican Explanation. Or consider the Chemical Revolution at the end of the 18th century. We no longer, after all, believe in Phlogiston, the fictional Imponderable Fluid that Georg Ernst Stahl, Joseph Priestley and other Natural Philosophers at the time believed to be at Work in combustion and calcination Phenomena. Antoine Lavoisier’s Scientific Truth about Oxygen prevailed over false Beliefs about Phlogiston.
The main actors of these Scientific revolutions often fostered this way of Thinking about Science as an enquiry leading to the Inevitable Triumph of Truth over past errors. Two centuries after Galileo’s successful Defence of the Heliocentric system, this idea of the course of Scientific Truth continued to Inspire Philosophers. In his Cours de Philosophie Positive (1830-42), Auguste Comte saw the Evolution of Human Knowledge in three main stages: ‘the Theological, or fictitious; the Metaphysical, or abstract; and the Scientific, or Positive’. In the ‘Positive’, the third and last Stage, ‘an Explanation of Facts is simply the establishment of a Connection between single Phenomena and some General Facts, the number of which continually diminishes with the Progress of Science’.[…]
Let us start with some Genuine Philosophical Questions about Truth in Science. Here are three: 1) Does Science aim at Truth? 2) Does Science tell us the Truth? 3) Should we Expect Science to tell us the Truth?
In each of these questions, ‘Science’ is a Generic Placeholder for whichever Scientific Discipline we are interested in Questioning. Question one might strike us as otiose but, in fact, it triggered one of the liveliest Debates of the past 40 years. Bas van Fraassen launched this Debate as to whether Science aims at Truth with his pioneering book The Scientific Image (1980). Does Science aim to tell us a True Story about Nature? Or does it aim only at saving the Observable Phenomena (namely, providing an account that makes Sense of what we can Observe, without expecting it to be the True account about Nature)?
Does Science Aim at Truth?
A Positive Answer to the first Question defines the Philosophical Stance known as ‘Scientific Realism’. Scientific Realists maintain that the Best Scientific Theories aim at truth as their final Goal. But Van Fraassen pointed out (following the French Philosopher Pierre Duhem), that often in Science Truth is not needed, and ‘Saving the Phenomena’ (or appearances) suffices. For example, Ptolemy’s Astronomy could account for the Appearance of Planets moving in Loops in the Sky over Months. This was called ‘Retrograde Motion’, and Ptolemy’s Theory accommodated it by introducing a series of Geometrical Contrivances (epicycles and deferents) around which Planets were Supposed to move. In fact, there are no such Circles of Circles, and Retrograde Motion is just an Illusion caused by the Relative Speeds of Planets all orbiting the Sun. As Copernican astronomy realised several centuries later, Ptolemaic astronomy was false, despite its century-long success at ‘saving the observable phenomena’.
There are philosophers today who embrace the view that Science does not need to be True in order to be Good. They argue that asking for Truth is Risky because it commits one to believing in Things (be it Epicycles, Phlogiston, ether or something else) that might prove False in the Future. In their view, ‘Empirically Adequate’ Theories, Theories that ‘save the Observable Phenomena’, are good enough for Science.[…]
Does Science Tell us the Truth?
When it comes to the Second Question does Science tell us the Truth? Scientific Realists and Anti-Realists of various Stripes have debated it. Leaving aside the Aim of Science, let us Concentrate on its Track record Instead. Has Science told us the Truth? Looking at the History of Science, does it amount to a persuasive story of Truth accumulated over the Centuries? Philosophers, Historians, Sociologists and Science-Studies scholars have all challenged a simple Affirmative Answer to this Question. They have in particular challenged the notion of Factual Truth implicit in the Question. In this debate, Philosophers take a Well-Defined set of facts about Nature as Responsible for making Scientific claims True or False, and Scientific Progress consists in unveiling more of these Facts until they are all finally Revealed.[…]
The History of Science, the Practice of Science, and Science policy all provide Reasons for disenchantment with Truth in Science. That is why, in our time, Philosophers of Science who call themselves realists tend to add some Qualifying adjective to the Word ‘Realism’ (be it ‘Structural’, ‘Selective’, ‘Pragmatic’, ‘Perspectival’ or ‘Local’). The net Result, the Dethroning of Truth, has left Philosophical Discussions about its Nature to Logicians, Philosophers of language and Metaphysicians, as opposed to Philosophers of Science.
Should we Expect Science to tell us the Truth?
The Third Question is whether we should Expect Science to tell us the Truth, or is Truth (or at least the notion of Factual Truth) not best left to logicians and Metaphysicians?
While critical analyses of Factual Truth are indeed best left to logicians and Metaphysicians, Philosophers of Science should not abdicate their Responsibility to talk about Truth in Science. The quasi-Wittgensteinian Myth of Atomic facts as the Truth-Makers of Scientific Claims has proved Inadequate to even scratch the Surface of very Complex practices in Science. But that is not a good reason (or pretext) for forgoing Truth Altogether. Nor is it a reason for concluding that science should not be expected to tell us the truth. Philosophers of science have a social responsibility to talk about truth in science. Questions about truth cannot be left unspoken, delegated, or, worse, met with discontent and misgivings. For a serious engagement with the topic of truth in science – thorny and difficult as it might be – must be the starting point of any serious engagement with Science in Democratic, Tolerant and Pluralistic Societies.
But whose Truth? By Whose Lights? Some might be tempted at this point by a Jamesian pragmatist Theory of Truth. American Pragmatism has traditionally provided an alternative way of Thinking about Truth, which some Philosophers of Science see as more Congenial to Capturing the Complex Nuances and the Power Structure of Scientific Practice. There are Significant and important differences among Pragmatists such as John Dewey, William James and Charles Sanders Peirce when it comes to truth (see Cheryl Misak’s Aeon Idea for an Excellent Introduction), and one should avoid Assimilating or Caricaturing this Diverse and Nuanced range of Philosophical Views. In James’s words: ‘“The True” … is only the expedient in the way of our Thinking, just as “the Eight” is only the Expedient in the Way of our Behaving.’ Stripped of its Rhetorical Flourishes, for James to be True is (to a good approximation) to work successfully. A Scientific Model is True, on a loosely Jamesian view, if it successfully Facilitates and enables activities (be they epistemic or not). If the Billiard-Ball model of Brownian Motion helps Scientists to predict the Behaviour of Gas Molecules, for example, the Model is (pragmatically) True. The falseness of the Presumption of Perfectly Spherical Molecules does not Matter. Is the Jamesian Conception of Truth more Congenial to Science, and more Conducive to Pluralism in Democratic Societies?
The Risk with a James-inspired conception of truth, as I see it, is that it is too malleable to Resist the tides of Time and the Stresses of Social Forces endlessly at Work in Science. A James-inspired view of Truth abdicates the Expectation that Science tells us the Truth in the name of a non-better-Qualified kind of Success of a Scientific Practice. But how to tell apart cases where Success does indeed track Truth from cases where it does not? More to the point, when it comes to matters such as Climate Change, the benefit of vaccinating children, or economic forecasts, we seem to need more than a malleable Jamesian conception of truth for the sake of Scientifically informed decisions that do not bow to pressure from Powerful Lobbies and Political Agendas (in the name of what ‘might work’). But, someone might reply, how can Truth and Pluralism go hand in hand if not by opting for a Jamesian conception of truth (if we really care about truth at all)?
There is another way of Thinking about how Truth and Pluralism might go hand in hand, without reducing matters of Truth to Calculations of what is Pragmatically good to Individuals or Communities sharing a Scientific Perspective at some Point in Time. First, it is necessary to understand the Key term ‘Scientific Perspective’ and how it impinges on Scientific Pluralism. In its original use by the philosopher Ronald Giere in 2006, ‘Scientific Perspective’ is akin to Kuhn’s disciplinary Matrix: a set of Scientific Models (including the Relevant Experimental instruments to gather data). In broader terms, Scientific Perspective is the Disciplinary practice of a Real Scientific Community at any given Historical Time. It includes the Knowledge they Produce, and the Theoretical, technological and Experimental Resources they use, or that guide their Work.
Thus, in Physics, one can speak of the Newtonian perspective vs the Einsteinian Perspective; in Chemistry, the Priestley vs Lavoisier Perspective; in Economics, the Keynesian vs the Monetarist Perspective; or the classical-genetics vs Molecular-Genetics Perspective in Biology, and so Forth.
What is to be said about the flourishing array of Scientific Perspectives? One thing is certain: Science works through Producing a Plurality of Perspectives. Over time, it leads to Scientific Progress, a process Comte mistakenly theorised into a monist picture of ‘Positive Science’. But a Plurality of Scientific Perspectives does not solve the problem of Truth. On the contrary, it invites Worrisome thoughts that Truth is either redundant to Scientific Perspectives; or, worse, relativised to Perspectives. One might ask again: whose Truth? By whose lights?
The time for a Defense of Truth in Science has come. It begins with a commitment to Get Things Right, which is at the Heart of the Realist Programme, despite mounting Kuhnian challenges from the History of Science, considerations about Modelling, and Values in Contemporary Scientific Practice. In the Simple-Minded sense, getting things right Means that Things are as the Relevant Scientific Theory says that they are. Climate Science is True if what it says about CO2 Emissions (and their effects on climate change) corresponds to the way that Things are in Nature. For the sake of Powerful Economic Interests, Sociopolitical consequences or simply different Economic Principles, one can try to discount, Mitigate, Compensate for, Disregard or Ignore altogether the Way that Things Are. But doing so is to forgo the Normative Nature of the Realist commitment in Science. The Scientific World, we have seen, is too Complex and Messy to be Represented by any Quasi-Wittgensteinian Picture of Atomic Facts. Nor can the Naive image of Comte’s Positive Science render Justice to it. But acknowledging Complexity and historical nuances gives no Reason (or Justification) for forgoing Truth Altogether; much less for concluding that Science Trades in Falsehoods of some Kind. It is part of our Social Responsibility as Philosophers of Science to set the record straight on such Matters.
We should expect Science to tell us the Truth because, by Realist Lights, this is what Science ought to do. Truth – understood as getting things right – is not the aim of Science, because it is not what Science (or, better, Scientists) should Aspire to (assuming one has Realist Leanings). Instead, it is what science Ought to do by Realist Lights.
Thus, to judge a Scientific Theory or Model as True is to judge it as one that ‘Commands our Assent’. Truth, ultimately, is not an Aspiration; a Desirable (but maybe unachievable) Goal; a figment in the Mind of the Working Scientist; or, worse, an Insupportable and Dispensable Burden in Scientific Research. Truth is a Normative Commitment inherent in Scientific Knowledge.
Constructive Empiricists, instrumentalists, Jamesian Pragmatists, Relativists and Constructivists do not share the same Commitment. They do not share with the Realist a suitable notion of ‘Rightness’. As an example, compare the Normative Commitment to Get Things Right with the view of the Philosopher Richard Rorty, in whose hands Putnam’s truth as “Idealised Warranted Assertibility” reduces to what is Acceptable to “Us as we should like to Be … us Educated, sophisticated, tolerant, wet liberals, the people who are always willing to hear the other side, to think out all the implications”’. Getting Things Right is not a norm about us at our Best, “Educated, Sophisticated, Tolerant, Wet liberal”. It is a Norm inherent in Scientific Knowledge.
To claim to know something in Science (or about a scientific topic or domain) is to claim for the Truthof the relevant beliefs about that Topic or Domain.
Thinking of truth as a normative Commitment inherent in the very notion of Scientific Knowledge brings some Benefits. It overcomes a false dichotomy between Atomic Facts and Non-Factive, Non-Truth-Conducive Inferences. And it makes Realism compatible with Perspectivism.[…]
Scientists Endorsing different Scientific Perspectives (and I stress the adjective Scientifichere to undercut a possible rejoinder that might trade on the Ambiguity of the word ‘Perspective’) do not construct perspectival facts. To do so would be to possibly commit Scientific Fraud. Rather, they ought to share a commitment to the same Tribunal of Evidence. They might adopt different experimental Strategies, different Models, different Theories. They might endorse different Values about what really matters in a Given Field. But it is the Tribunal of Evidence that they all ultimately ought to respond to. Getting the Evidence Right, in the first instance, via accurate Measurements, sound non-ad-hoc procedures, and robust Inferential strategies, defines any research Programme that is worth Being called ‘Scientific’.
The Realist Commitment to get Things Right must begin with getting the Evidence Right. No Perspective worthy of being called ‘Scientific’ survives fudging the Evidence, Massaging or Altering the data or discarding Evidence.[…]
Michela Massimi is Professor of Philosophy of Science at the University of Edinburgh in Scotland. She works in history and Philosophy of Science and was the recipient of the 2017 Wilkins-Bernal-Medawar Medal by the Royal Society, London, UK