By Paul Newall (2005)
According to lore, Imre Lakatos was an excellent speaker and a highly amusing one. (He would often listen in on Paul Feyerabend's talks from his office and shout rejoinders if the latter got too carried away.) He wrote a series of lectures on scientific method that were collected in Motterlini's For and Against Method, which we consider here as a means of discussing demarcation in science. It covers some of the discussion in his public talk Science and Pseudoscience
The first lecture dealt with the Demarcation Problem, which Lakatos rendered as "what distinguishes science from pseudoscience?" He then provided four examples of why it is important (and "not an esoteric problem for just armchair philosophers"): the historical debates over Copernicanism; the Lysenko affair in the Soviet Union; the studies done concerning the link, if any, between IQ and race; and finally Velikovsky's ideas. We could add another that most of us are familiar with: the question of creationism in schools, in which it is said that creationism should not be allowed in the science classroom because it is not scientific at all but rather pseudoscience. To make this sort of claim, however, requires – implicitly or otherwise – a demarcation criterion (or criteria) that allows us to specify what is or is not science.
Lakatos remarked – casually, as it were – that Karl Popper was once a cabinet maker, helping us to imagine Sir Karl constructing a special example of his craft into which we would feed theories and have the thing tell us if they are meaningful or not - a "sausage machine", as it were, heaping theories into piles marked "science" and "pseudoscience". This was not just a subtle dig for the amusement of his students: the demarcation problem can be viewed in this way to make it clearer what the issue is. Given a theory, what formula do we have to run it through before we can say "this is a scientific theory" and (provisionally) accept it as interesting or "this is pseudoscience" and (presumably) dismiss it? Lakatos contrasted Hegel's ideas – those we would now consider obviously pseudoscientific and hence a straightforward example – with Velikovsky's, whose case was not so simple. According to Popper's falsificationism, for instance, Velikovsky’s theories were scientific; and yet they were rejected by most astronomers. Later Lakatos came back to problems with falsification and why we need more, but at this point he hinted that demarcation in the natural sciences would be much easier than in the social sciences. His joking example of burning down the London School of Economics (LSE) shows again how important the demarcation problem is in general: when politicians decide to invade another country, say, they have – like it or not – used a demarcation criterion (or criteria) to decide where the line was and when it was crossed such that they had to act.
Lakatos went on to explain some of the positions historically taken on the demarcation problem. The militant positivists believed (and still believe) both that we can find demarcation criteria and that we ought to divide up theories into good or bad accordingly. We also have skepticism, to which Lakatos gave other names. This was a (likely deliberate) straw man, but we come back to it later and consider whether it was a fair description of what sceptics like Feyerabend actually said (as well as if there is such a thing as epistemological anarchism). He then spoke of intellectual honesty, or whether it is acceptable morally to propose pseudoscientific theories or try to convince others of them. (For Popper it was - and many commentators today still is - wrong to advocate pseudoscience, however well-intentioned we might be in doing so.)
Returning to demarcation criteria, Lakatos then talked about elitist authoritarianism (which is somewhat similar to Dickie’s Institutional Theory in the philosophy of art): what is or is not science is demarcated by scientists (just as what is or is not art is decided by artists and museum directors, according to Dickie). This is a method of demarcation (favoured by Polanyi) but does not give - or rely upon - demarcation criteria at all. He gave some justification for this position before bringing it crashing down with two questions:
- How do scientists (or philosophers, or whomever) come to disagree with one another?
- How do scientific revolutions come about?
In the first instance, it often happens that some scientists hold to one theory while others support another (or even still others). If all the scientists concerned are "good" scientists (whatever that means), how do we decide which theory is scientific and which pseudoscientific? Elitist authoritarianism appears to give us no guidance. For the second, Lakatos gave a brief (and - it must be said - dismissive) introduction to Kuhn and asked an important question for all forms of demarcation criteria: how do we get started in science? That is, suppose we begin over and ask how we decide which theories are scientific and which pseudoscientific. There are no scientists to help us decide, after all. What can be done?
In his second lecture, Lakatos began by saying a few words about positivism and Popper's determined opposition to it. (The amusing subscripts he used were (as the footnote says) thrown right back at him by Feyerabend later.) Hopefully it is at least clear on reading that Lakatos had a wicked (yet subtle) sense of humour, which he employed often. This was likely one of the qualities that brought about his friendship with Feyerabend. Lakatos explained that he would set out the various possible answers that have been given to the demarcation problem. If we find that they all fail, he said, we have to accept Feyerabend's or Polanyi's alternative. We need not concern ourselves with whether Lakatos was giving a falsely limited choice here (i.e. other suggestions could come along at a later date or the problem itself might need redefining or dispensing with altogether), reading it instead as accompanied by much winking at his audience.
Talking a little about the so-called Dark Ages, Lakatos noted that in the seventeenth century the standard used for science was a form of justificationism, according to which knowledge is justified by reference to fixed standards. These standards could be experience, holy texts, or even - said Lakatos - the balance of probabilities. He then remarked: "So it is quite clear that these standards have theological origins."
The idea here is that - in the past - appeal was made to scripture to justify a statement because to utter a false comment on a religious matter could lead to damnation. Some, like Popper (in Lakatos' opinion), believed or believe something very similar about scientific theories - that it is wrong to publish or hold to a pseudoscientific theory. Lest this seem overly dramatic, we can refer back to the examples in the discussion of the first lecture and see that perhaps it is not. In particular, we need only consider the reactions on the part of some members of the scientific community to advocacy of Intelligent Design, so-called, to see a fervour in opposition that could easily be described as "religious" and the envy of many a pious churchman of the Middles Ages.
Lakatos then talked about inductivism, pointing out that to justify a theory by reference to facts we require two important steps:
(1) from a fact to a factual proposition describing the occurrence; and (2) from a factual proposition which is spatio-temporally singular to a spatio-temporally universal proposition.
This is, of course, the celebrated problem of induction. Note, however, that Lakatos was distinguishing two difficulties, while we usually only talk about the second. To use his example, the steps are:
(1) - from "chalk exists", "blackboards exist", "I exist", and so on, to "this is a piece of chalk and it writes on the blackboard"; and
(2) - from "this is a piece of chalk and it writes on the blackboard" to "all pieces of chalk write on the blackboard".
Can these be bridged? Apparently not, since inductive inferences have long be known to be invalid. (Mill's 1843  system of logic, however, is considered by some to be the best approach to the problem of induction.) The second step is what we usually think of as the inductive inference involved in science, but the first is necessary also. Lakatos concluded that inductivism (or justificationism) will not suffice as a demarcation criterion and hence should be rejected, a position accepted by all.
Lakatos began lecture three by expanding on his previous remarks about the unbridgeable steps from facts to factual propositions and from the latter to inductive justifications. He then went on to discuss theory formulation, first considering the idea (inductivist and still quite common) that we observe the facts and use them to build theories. In the case of planetary hypotheses, he said, people instead were already sure that planets had to move in circles (due to Aristotle's ideas, and others) and looked for evidence to justify it. This is interesting because it tells us something about the way science proceeds: according to the inductivist, science starts with facts and induces theories from them, but this example from the history of science shows that actually astronomers were convinced already (for mathematical, philosophical and other reasons) that planets move in circles and used their observations to justify this. Another section on the myth that Einstein's theory of special relativity was derived from the famous Michelson-Morley experiment is tackled in more detail by Holton. This is part of a general discussion (Lakatos' other main instance was the notion that Newton's laws were derived from Kepler's) of inductivism giving birth to historical yarns that have little or no foundation. When we note in this way that famous instances of scientific work fail to match the methodology we insist science follows, we either have to give up the methodology or stop calling the work scientific.
The notion that the probability of a theory is always zero was, as Lakatos noted, derived by Popper and included as an appendix in his The Logic of Scientific Discovery. (A look at the interpretations of probability - emphasing the difficulties - is here. It is important to understand that Lakatos was treating of the assignment of probabilities to scientific theories on the basis of the available evidence, not confidence intervals.) The idea, in brief, is that there are infinitely many theories that may account for the available data set (this is the problem of underdetermination, of course). Following Goodman (1983), a nice way to appreciate the difficulty is to suppose that the data are points on graph paper and then ask how many lines may be drawn between all of them. The answer, trivially, is an infinite number. It would follow that the probability of any one being correct is zero.
It seems the misunderstanding arises when confusing a theory with an hypothesis. A confidence interval is used to accept or reject a null hypothesis, not a theory. Perhaps Lakatos was guilty of being careless with this distinction? For instance, he says that a "scientific hypothesis says..." and immediately follows his example by remarking that the "information content of such a theory..." The inverse squared law of gravitational attraction (his example) is clearly a law. The possession of a characteristic, on the other hand, is neither a law nor a counter-example. A finite (although large) number of confirming instances makes no difference - a single counterinstance will disprove the hypothesis. The accumulation of confirming observations runs smack into the problem of induction, since the prior results do not make the next any more likely to possess the desired characteristic unless we assume it to be law-like in the first place - thereby begging the question. (See the discussion of confirmation.) As Lakatos also said, however, there have been attempts to develop an inductive logic - by Tarski and more recently by Hintikka and others (see Lakatos, 1968).
In his fourth lecture, Lakatos used the discussion of verificationism to get in a few choice jibes at the positivists' expense. Beginning with Schlick's version, he explained that it was quickly shown to be untenable because inductive inferences (particularly laws) cannot be meaningful under such a demarcation criterion (that is, to verify a statement like "all swans are white" – the example he used – we would need to see all swans and verify their whiteness individually). A healthy disdain then followed for Ayer's ( 1946) attempts to rescue verificationism, noting that those propositions that the positivists wanted to exclude (like religious or ethical ones) could be made meaningful under Ayer's terms. This was a reductio argument.
In the next look at "super direct" verificationism, Lakatos' humour came again to the fore:
In 1492, however, Columbus had discovered America, and that led to some trouble because in 1949 an American named Alonzo Church reviewed Ayer's book...
Here Lakatos was alluding to Church's proof (1949) that all statements would be verifiable, the reaction to which was, according to Lakatos, an increasing "scholasticism", eventually culminating in a nine-page definition of verification including logical conditions that would have to be satisfied. Although Lakatos had some fun with this, his point was clear: such criteria are no use at all to scientists or anyone else trying to sort theories into good and bad (or deciding which books to burn, alluding to Hume’s famous declaration).
Moving on to conventionalism, Lakatos discussed in a lengthy aside the rise of instrumentalism via the Ptolemaic astronomical system. Here we see a rare instance of error: contrary to the claims of some philosophers of science, Ptolemy did not accept that his theory was only a tool and instead tried to develop a realistic understanding of it - nor, for that matter, did Copernicus "get in trouble" simply because his theory apparently contradicted certain Scriptural passages (instead his theory was unconvincing for reasons that are explained in the essay on Galileo). In any case, and in spite of Lakatos' mistakes, the point of conventionalism is to use theories as instruments and not worry about whether they are true or not in reality - we call them true by convention.
This explanation was followed by still more stories, including the realisation in the nineteenth century that any convention could be saved by enough ad hoc hypotheses, so that conventionalism fails to demarcate at all. (This does not address the question raised in Lecture two, however, by pointing to the demise of instrumental theories.) Moreover, the problem for conventionalism is what to do with established theories. Since these are accepted by convention, we seem drawn into the conclusion that experiment can refute a new theory but not an old one - that is, the power (and relevance) of empirical investigation seems to lessen the more science develops and expands. Unfortunately the fifth lecture - entitled The Limits of Conventionalism - was lost, in which Lakatos expanded on this matter.
In lecture six, Lakatos began his critque of Popper's falsificationism by reiterating that the demarcation problem has typically involved a moral claim; namely, that it is wrong (or irresponsible) to insist upon a theory that is unproven; and since ideas have consequences, we should be careful when speculating. (Sadly Lakatos followed Feyerabend (1987) here by accusing Galileo of not following this advice, saying that "Galileo's crime was to propound Copernicus's system not as a calculating device, but as the truth about the universe." It is explained elsewhere why this interpretation is mistaken.)
For Popper, there was a failure of intellectual honesty in advocating unfalsifiable propositions. By considering Bohr's theory of the atom at length (and in some depth), alongside his own experiences in Hungary, Lakatos showed how difficult it would be to force the historical process that led to Bohr's theory into the straightjacket of falsificationism. Remarking on another example, Lakatos pointed out that Newton's laws were falsified by the discovery in 1816 of the anomalous perihelion of Mercury; and yet the laws were maintained until the discrepancy could be accounted for in 1916 by Einstein's theory of gravitation. This makes for a century of moral failure on the part of those who refused (or neglected) to do their duty and give up a falsified idea. Such stories are part of the historical approach in the philosophy of science. By demonstrating an inconsitency between a philosophical account of what science is supposed to be and how scientists actually behave, we are forced to admit either that scientists behaved irrationally or to give up the account.
In the last lecture, Lakatos continued his demolition of Popper by again referring to some of the issues discussed in our look at falsificationism, specifically the question of ceteris paribus clauses:
... suppose we take Newton's three laws of dynamics, plus the law of gravitation, plus twenty-seven initial conditions, plus thirty-seven observational theories, and we derive an observational statement which is inconsistent with all this, what should we do? Should we cross it all out?
We learn that Popper's interest in the demarcation problem grew from a frustration in talking about politics and/or psychoanalysis in his early student years with people who always seemed to be able to find a way out of any difficulty he could bring up, which led to an interest in theories being decidable. What Popper tried to develop thereafter was a demarcation criterion that would call Newton's or Bohr's theories scientific but not Marx's or Adler's. Lakatos was able to show via examples such as those already detailed above that the insistence on falsification would render all theories unscientific. Popper tried to avoid this - desperately, at times - by implicitly claiming for himself the right to decide whether an anomaly is serious or not, even insisting in a television interview that Mercury's perihelion was not. What we see, then, is that Popper's falsificationism degenerates into a version of authoritarian conventionalism, since he could not avoid relying on the judgement of scientists (or, more often, his own...) as to when we should consider a falsifier strong enough to bring to bear all the weight of moral authority in demanding the theory's rejection and when to "wait and see" instead.
In closing this section, Lakatos remarked as follows:
I think that the fact Popper's philosophy survived for so long is a sociological mystery. Popper's immortality is secured by this idiotic result.
Lakatos was writing in 1973. Even today, however, Popper's name is spoken with reverance and his falsificationism appealed to as either the definitive statement on what characterises science ("a theory should be falsifiable if it is to be considered scientific") or an important part thereof. The same moral indignation at refusing to dispense with unfalsifiable ideas can be found wherever science is discussed in vaguely philosophical terms. The strange thing is that - however harsh Lakatos' words may seem - the high regard for falsificationism in one form or another persists in spite of philosophers of science have thoroughly destroyed it as a credible demarcation criterion. The commitment to it is perhaps explained by the political and rhetorical importance of demarcation in the public sphere.
Given the failure of so many demarcation criteria, is this really a problem at all? There are two main reasons why it is: firstly, we do demarcate (especially given that time and resources are finite, leading to the question "how long is long enough?"); and secondly, this demarcation has consequences. A budding theory on the right end of a demarcation can potentially benefit from funding, further research and the support of the so-called scientific community; while conversely a declaredly pseudoscientific idea can be mocked, vilified in the (scientific and general) press and be unlikely to improve its station due to a lack of financial backing (although this does not always hold), while the layman or - worse - scientist responsible can expect personal and professional attacks. This latter phenomenon, indeed, is the modern-day equivalent of the Popperian moral revulsion at advocating pseudoscience - considered by many to be dishonest at best, if not the very definition of "anti-scientific" behaviour.
There can be little doubt that demarcation criteria still play an important role in science, finding their way into the debate over climate change and with critiques of creationism and intelligent design repeatedly calling on a form of falsificationism (usually the most simplistic). An increasing number of studies are showing the way in which rhetoric shapes science, too, and particularly the importance of rhetorical dimensions in achieving demarcation (especially implicit or explicit claims of authority). When we take the time to examine these controversies, we find that the philosophical failure of demarcation criteria does not prevent them being employed, even if this may backfire or encourage an uncritical tone throughout. As usual, the possibility of genuine dialogue is the victim.
What we learn from Lakatos' lectures is that the demarcation problem is alive and well, even if the most frequent usages of demarcation are na�ve and propagate long-dead myths of their efficacy in distinguishing between science and pseudoscience. The importance of going over these failures, however, lies in Mill's principle that a truth unrehearsed and unchallenged becomes a dogma far too easily. That it is so difficult to define what science is shows us not a failing but the very strength of this mode of inquiry in the first place.
- Ayer, A.J., Language, Truth and Logic (London: Gollancz, 1946).
- Church, A., Review of Ayer, Language, Truth and Logic in Journal of Symbolic Logic, 14(1), pp52-53, 1949.
- Feyerabend, P.K., Farewell to Reason (London: Verso, 1987).
- Goodman, N., Fact, Fiction and Forecast (Cambridge, MA: Harvard University Press, 1983).
- Lakatos, I., The methodology of scientific research programmes (Cambridge: Cambridge University Press, 1978).
- Lakatos, I., The Problem of Inductive Logic (Amsterdam: North-Holland Publishing Company, 1968).
- Mill, J.S., A System of Logic (Honolulu: University Press of the Pacific, 2002).
- Popper, K.R., The Logic of Scientific Discovery (New York: Basic Books, 1959).