There is a conventional, general and eminently satisfactory picture of science as a steady progression from crude guesses to sophisticated knowledge, propelled by ever-more ingenious techniques and machinery. Science, like the ocean waves approaching the shore, moves in only one direction, and if foolish humans attempt to erect barriers to its progress, it is only a matter of time before their obstructions are swept aside and the great tide of discovery flows on.
Much of the history of Western philosophy assumes such a process. Descartes, considered the pivotal figure in the development of ‘modern’, ‘rational’ thinking firmly asserted that ‘knowledge’ was out there to be identified by those able and willing to put aside their ‘false beliefs’ and note what was left ‘clearly and distinctly’ instead. Then, once firm foundations had been established, the rest of the edifice can be constructed without needing to worry about one or other bit of it later being shown to be wrong. The approach is, in fact, borrowed from the Ancient geometers like Ptolomy, who had explained that powerful calculations can be made if one starts with certain clear principles or ‘axioms’ and then allow noting else to count as known which cannot be logically deduced from these. What better model for science! No matter that Ptolomy thought the Earth was fixed immovably at the centre of the universe, and that the stars rotated around it on crystal spheres making divine music as they turned. And that all of that, although nonsense in many ways, did fit in with his original theory.
Ever since, mathematical ideals have guided philosophers and scientists firmly towards grand schemes based on simple principles and away from the complexities and inconsistencies of ‘real life’. Take Immanuel Kant, for instance. Kant, whose original and founding concerns are all scientific (even if he is remembered nowadays more as a ‘pure philosopher’) offered many erroneous deductions from his theories, such as that all the planets in the solar system had life on them, with the intelligence of the life on them increasing the further away the planet was from the sun, or that people had only a fixed amount of sleep in them at birth, and would die early if they used it up by lying in bed too long. Or then there is Gottfied Leibniz who deduced a universe made up of ‘a single substance without parts’ that he called ‘monads’. Here is how he introduces them in the Monadology:
The body belonging to a monad (which is the entelechy or soul of that body) together with an entelechy constitutes what may be called a living being and together with the soul constitutes what may be called an animal. Now the body of a living being or an animal is always organised; for, since every monad is a mirror of the universe in its way, and since the universe is regulated in perfect order, there must also be an order in the representing being, that is, in the perceptions of the soul, and consequently in the body in accordance with which the universe is represented therein.
Monads are the ultimate building blocks of the universe, and are only be found through pure logic. Leibniz explains how matter could be made up of colourless monads, with the metaphor of the rainbow. It appears to us a bright spectrum of colour in the sky, but in reality is made up of many millions of tiny droplets of water. And each of these is certainly colourless.
Like Descartes, Plato, and so many philosophers before and since, Leibniz preferred to fit the universe into his theory, than allow the universe to form his theories. So, for example, Leibniz explains that although the monads do not appear to the senses ('they are colourless') we assume their existence in order to explain reality and the meaningfulness of language.
Monads are living centres of energy and activity. Unlike atoms, they do not interact, and cannot be 'split'. God is allowed only the role of having designed the machine. But Leibniz sees his machine very differently from those of his contemporaries (including Descartes). Leibniz's universe is alive - and conscious. He had been much impressed by the new world of the microscope, through which his contemporary, Anton van Leeuwenhock, had revealed a host of tiny living organisms previously unsuspected.
There is a world of creatures, living beings, animals, substantial forms, souls in the very smallest part of matter. Each bit of matter can be thought of as a garden full of plants or as a pond full of fish – except that every branch of a plant, every part of an animal's body, every drop of the liquids they contain is in its turn another such garden or pond. And although the earth and the air occupying the spaces between the plants in the garden, or the water occupying the space between the fishes in the pond, is not itself a plant or a fish, yet they contain still more of them, only mostly too small to be visible. Thus there is nothing uncultivated, sterile or dead in the universe – no chaos or confusion, except in appearance. It is rather as a pond appears from a distance, when you can see a confused motion and milling around, so to speak, of the fishes in the pond, but without being able to make out the individual fishes themselves. One sees from this how every living body has a dominant substantial form which is the soul in the animal; but the members of this living body are full of other living bodies, plants and animals, each one of which also has its own substantial form, or dominant monad. 1
This then, is the introduction of new technology and new ‘experimental’ evidence into Leibniz’s mondology - but the effect is not to challenge the old theory but rather to reinforce it. After all, every physical body is a 'colony' of monads, living in 'pre-established harmony'.
Thus each organised body of all living beings is a kind of divine machine or natural automaton, which infinitely surpasses all artificial automata. For a machine constructed by man's art is not a machine in each of its parts. For example, the tooth of a brass wheel has parts or fragments which, for us, are no longer artificial things, and no longer have any marks to indicate the machine for whose use the wheel was intended. But natural machines, that is, living bodies, are still machines in their least parts, to infinity. This is the difference between nature and art, that is, between divine art and our art.
In fact, whatever we might understandably like to think, in science, as has been show again and again, experiments do not lead to new theories, because all historically significant theories (and quite a few insignificant ones too) have ‘agreed with the facts’. Because, as every politician and spin doctor knows, there are a lot of facts and they can be chosen to bolster your theory. Scientists are no different.
But they think they are.
Conventionally speaking, we suppose that when experiments are conducted to ‘test’ theories in reality, and that when the results do not accord with those anticipated, the theory is ‘disproven’. Or ‘falsified’ as Karl Popper puts it, in The Poverty of Historicism, taking issue with Descartes who thought it was enough to be very pleased with your theory (“to see it “clearly and distinctly”)
tests can be interpreted as attempts to weed out false theories - to find the weak points of a theory in order to reject it if it is falsified by the test. This view is sometimes considered paradoxical; our aim, it is said, is to establish theories, not to eliminate false ones. But just because it is our aim to establish theories as well as we can, we must test them as severely as we can; that is, we must try to find fault with them. Only if we cannot falsify them despite our best efforts can we say they have stood up to severer tests. This is why the discovery of instances which a theory mean very little if we have not tried, and failed, to discover refutations. For if we are uncritical, we shall always find what we want: we shall look for, and find confirmations, and we shall look for, and find, confirmations, and we shall look away from and not see, whatever might be dangerous to our pet theories. 2
Popper described himself as a 'critical rationalist', the ‘rationalists’ being thinkers such as Descartes, Leibniz and, above all, Kant. The term also signified his rejection of ‘classical empiricism’, as was being revived and refined by the logical positivists of the so-called ‘Vienna Circle’ in the 1930s. . Against all these, Popper argued that there are no ‘theory-free’, infallible observations as empiricists ask us to assume, but rather, all observation is theory-laden, and involves seeing the world through the distorting glass (and filter) of a pre-existing conceptual scheme.
Following up the subversive philosophy of David Hume, some centuries earlier, Popper categorically rejects ‘induction’ or the ‘inferring’ of general laws from particular cases, which is basis of scientific method. Such inferences , he says, should play no role in scientific investigation since it is logically impossible to ever secure the verification of a universal statement. Since all scientific theories are like this, making universal claims for their truth, they are unverifiable.
|"Science does not rest upon solid bedrock. The bold structure of its theories rises, as it were, above a swamp. It is like a building erected on piles...if we stop driving the piles deeper, it is not because we have reached firm ground. We simply stop when we are satisfied that the piles are firm enough to carry the structure, at least for the time being. 3"|
Like Hume, Popper stresses that no number of positive confirmations at the level of experimental testing can ever confirm a scientific theory, because, like Bertrand Russell's unfortunate chicken (awaiting the farmers wife for a handful of grain each morning) the next case along can still be very different (for the chicken, it’s future is to be Dinner). However, Popper makes more of the negative cases than does Hume, he thinks that every counter-instance is decisive: it shows the theory to be false.
Here, as the contemporary academic, Stephen Thornton, put it, the central thrust of Popper's argument is Socratic, knowledge seeking becomes a process of seeking out a counter-example to demolish old theories with the intention of producing in their place better ones. But in a way David ~Hume was more radical than Popper. He concluded that science and philosophy alike rested less upon the rock of ‘logic’ and method, but rather upon the shifting sands of scientific fashion and aesthetic preferences.
However, the modification of the Ptolomaic System, that is the Ancient Greek theories of how the heavenly bodies might be on crystal spheres, is itself a 'paradigm' example of how ‘falsification’ does not seem to take place , let alone decide the survival or otherwise of a theory. Instead, the Ancients simply increased the number of spheres each time observations showed a problem for the theory. It is here that the really rather psychological and obscure notion of the ‘paradigm shift’ comes in.
This subversive and attractive notion was released from the laboratory by the Twentieth century philosopher of science, Thomas Kuhn. Once out, it soon spread, virus like, from the ‘physical sciences’ to the social sciences, and on to the arts and even business management courses. It became so popular that people began to describe Kuhn’s idea of paradigm shifts as in itself a kind of paradigm shift’. In its simplest from the theory claims that scientific knowledge proceeds in fits and starts, with theories fighting to the death, as it were, against each other, rather than as a smooth process of the accumulation and refinement that people like to imagine.
Rather than being ‘logical’ or rational, scientists find, at a certain point, says Kuhn, either the old theory has become too complicated and cumbersome to modify, and collectively abandon it, or else a ‘split’ emerges between followers of one theory and another that is eventually decided in favour of the new theory for any number of reasons, none of them particularly scientific.
It is in his 1962 book, The Structure of Scientific Revolutions, that Thomas Kuhn offers a way to see how the apparently lofty and impregnable fortress of scientific consensus is really just a shifting façade.
Kuhn says that “a scientific community cannot practice its trade without some set of received beliefs ” and that these beliefs form the foundation of the "educational initiation that prepares and licenses the student for professional practice". The nature of the "rigourous and rigid" preparation helps ensure that the received beliefs exert a "deep hold" on the mind of each new member of the community.
What is considered to be ‘Normal science’ "is predicated on the assumption that the scientific community knows what the world is like"— and ‘responsible’ scientists take great pains to defend that assumption. New ideas, new paradigms/theories, have to be suppressed , “because they are necessarily subversive” of basic commitments.
To do otherwise would require the reconstruction of existing assumptions and the re-evaluation of accepted facts. This would be a huge task, possibly dangerous, possibly impractical. Certainly, time consuming. Thus it is to be strongly resisted by sensible members of the established community. “Novelty emerges only with difficulty, manifested by resistance.”
Nor can the scientists function without a set of beliefs, for a paradigm is essential to scientific inquiry - "no natural history can be interpreted in the absence of at least some implicit body of intertwined theoretical and methodological belief that permits selection, evaluation, and criticism".
Kuhn says that ‘evidence’ alone does not decide theories. He notes that Philosophers of science have repeatedly demonstrated that more than one theoretical construction can always be placed upon a given collection of data. Even if problems and weaknesses with a theory begin to accumulate, he says, it is easier for the establishment, scientific, religious, political, to either ‘modify’ the original idea, or even to suppress the conflicting information that to abandon their established orthodoxies.
So how, and why, do paradigms ever change?
Kuhn links the process of paradigm change in the scientific community to the nature of perceptual (conceptual) change in an individual, where change is resisted at first, but once the ‘jump’ is made, the old ways of thinking become impossible to return to. It is also, he suggests, analogous to a political revolution.
The Logic of Scientific Discovery (translation of Logik der Forschung, 1935, 1959) by Karl Popper
The Structure of Scientific Revolutions (1962) by Thomas S. Kuhn
Part of an early version of this article draws on research for Martin Cohen's book 'Mind Games' (Blackwell 2010) and is used under the principles of 'fair use'.