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April 5, 20081 Chapter Five Lakatos' Methodology of Scientific Research Programs and Generative Grammar 1. Introduction As mentioned in chapter 3, Lakatos' 'methodology of scientific research programmes' is concerned with a series of theories that change over time, while keeping its essential identity. What we are concerned with, on the other hand, is a much smaller issue of whether or not we have a repeatable phenomenon and how we can proceed in answering the question. Establishing, or discovering, a repeatable phenomenon is, as noted, identifying a piece of data that can be reasonably considered as part of the object of explanation in generative grammar. What must be recognized here is that the identification of a repeatable phenomenon (i.e., a repeatable phenomenon getting qualified or 'licensed' as such) is crucially based on our hypotheses about the CS (Computational System), what we know about parsing, and what we know about the effects of pragmatic factors such as are induced by the choice of certain lexical items. It is not clear if generative grammar can be regarded as having attained the status of a scientific research program in the terms of Lakatos 1970, 1978. Neither is it entirely clear whether and how well a methodology like Lakatos', which was based on examples from natural sciences, notably physics, can be applied to generative grammar, as pointed out by Y. Deguchi (p.c., October 2007). If we accept that his 'methodology of scientific research programmes' is indeed a 'universal definition of progress', as stated in Lakatos 1978: 178) (the emphasis is as in the original), however, we can actually ask whether generative grammar fits the description. In what follows, I would like to address the question, covering many of the characteristics of a scientific research program discussed in Lakatos' works. [What is provided from here on is basically excerpts from Lakatos' writing and some additional remarks provided by myself.] 1 This is the same as "Research_Programs" as of April 10, 2008. 493723914 1/7 2. Lakatos' scientific research programs 2.1. Lakatos' (1976/1978) rough explanation Lakatos' (1978; 1782) 'rough' explanation of 'the central features' of his 'methodology of scientific research programmes', which is said to be 'a new demarcationist methodology (i.e., a universal definition of progress)', starts with the following. (1) (p. 178) [M]y unit of appraisal is not an isolated hypothesis (or a conjunction of hypotheses): a research programme is rather a special kind of 'problemshift'. developing series of theories. It consists of a Moreover, this developing series has a structure. It has a tenacious hard core, like the three laws of motion and the law of gravitation in Newton's research programme, and it has a heuristic, which includes a set of problem-solving techniques. (This, in Newton's case, consisted of the programme's mathematical apparatus, involving the differential calculus, the theory of convergence, differential and integral equation.) Finally, a research programme has a vast belt of auxiliary hypotheses on the basis of which we establish initial conditions. The protective belt of the Newtonian programme included geometrical optics, Newton's theory of atmospheric refraction, and so on. I call this best a protective belt because it protects the hard core from refutations: anomalies are not taken as refutations of the hard core but of some hypothesis in the protective belt. Partly under empirical pressure (but partly planned according to its heuristic) the protective belt is constantly modified, increased, complicated, while the hard core remains intact. 2.2. Three components The components of a scientific research program are said to be the following. (2) 2 a. a hard core b. a protective belt of auxiliary hypotheses c. heuristic According to the editors' note on p. 168, the paper that contains this passage was first published in 1976, as a joint paper with Zahar. 493723914 2/7 (3) (p. 883) Mature science consists of research programmes in which not only novel facts but, in an important sense, also novel auxiliary theories, are anticipated; mature science ... has 'heuristic power'.4 2.3. The hard core and a protective belt of auxiliary hypotheses (4) (Lakatos 1978: 45) Newtonian science ... is not simply a set of four conjectures – the three laws of mechanics and the law of gravitation. These four laws constitute only the 'hard core' of the Newtonian programme. But this hard core is tenaciously protected from refutation by a vast 'protective belt' of auxiliary hypotheses. And, even more importantly, the research programme also has a 'heuristic', that is, a powerful problem-solving machinery, which, with the help of sophisticated mathematical 3 If it is not specified otherwise, the page number is to Lakatos 1978. 4 The emphasis is as in the original. I understand that what gives rise to the anticipation is the negative heuristic that the hard core of the research program should be protected from refutations and the positive heuristics, which, according to what I have seen in Lakatos' remarks here and there, presumably include theories of what might affect the ultimate measurements of what the hard core is concerned with (e.g., the Newton's theory of optics in the Newtonian research program whose hard core consists of the three laws of motion and the theory of gravitation), mathematical techniques adopted – which no doubt should be modified and revised as the research goes on, along with the hard core. In the context of addressing whether and how generative grammar would fit in Lakatos' characterization of scientific research programs, it would be natural to ask questions such as: --What is the hard core in generative grammar? --What is the negative and positive heuristics in generative grammar? etc. 5 "Science and Pseudoscience" (transcript) http://www.lse.ac.uk/collections/lakatos//Default.htm. by Imre Lakatos. Obtainable at Published in Lakatos 1978, as "Introduction." Lakatos, Imre. 1978. The Methodology of Scientific Research Programmes: Philosophical Papers Volume 1, edited by John Worrall and Gregory Currie, Cambridge University Press. are to Lakatos 1978. 493723914 3/7 The page references here techniques, digests anomalies and even turns them into positive evidence. For instance, if a planet does not move exactly as it should, the Newtonian scientist checks it conjectures concerning atmospheric refraction, concerning propagation of light in magnetic storms, and hundreds of other conjectures which are all part of the programme. He may even invent a hitherto unknown planet and calculate is position, mass and velocity in order to explain the anomaly. (5) (p. 5) a. Each of [Newton's theory of gravitation, Einstein's relativity theory, quantum mechanics, Marxism, Freudianism], at any stage of its development, has unsolved problems and undigested anomalies. All theories, in this sense, are born refuted and die refuted. b. [A]ll the research programmes I admire have one characteristic in common. They all predict novel facts, facts which had been either undreamed of, or have indeed been contradicted by previous or rival programmes. (6) (p. 41, note 2) [W]e retain a syntactically metaphysical theory as the 'hard core' of a research programme as long as its associated positive heuristic produces a progressive prblemshift in the 'protective belt' of auxiliary hypotheses.6 2.4. The hard core (7) (p. 48, note 4) The actual hard core of a programme does not actually emerge fully armed like Athene from the head of Zeus. It develops slowly, by a long, preliminary process of trial and error.7 (8) (p. 110) a conventionally accepted (and thus by provisional decision 'irrefutable') 'hard core' 6 The italic is as in the original, and the underscore is provided here. 7 One should naturally wonder what the hard core of generative grammar (as of 2008, for example) would be, if any, and whether it has indeed developed "slowly, by a long, preliminary process of trial and error." 493723914 4/7 (9) Usually, we are faced with what I call a hard core of two, three, four or maximum five, postulates. (Lakatos and Feyerabend 1999: 103) 3. A Heuristic 3.1. Positive and negative heuristic (10) (p. 47) a. some tell us what paths of research to avoid (negative heuristic) b. others [tell us] what paths to pursue (positive heuristic) 3.1.1. A negative heuristic (11) (p. 48) The negative heuristic of the programme forbids us to direct the modus tollens at this 'hard core'. Instead, we must use our ingenuity to articulate or even invent 'auxiliary hypotheses', which form a protective belt around this core, and we must redirect the modus tollens to these. It is this protective belt of auxiliary hypotheses which has to bear the brunt of tests and get adjusted and re-adjusted, or even completely replaced, to defend the thus-hardened core. A research programme is successful if all this leads to a progressive problemshift; unsuccessful if it leads to a degenerating problemshift. 3.1.2. A Positive heuristic (12) (p. 110) [A] 'positive heuristic' ... defines problems, outlines the construction of a belt of auxiliary hypotheses, foresees anomalies and turns them victoriously into examples, all according to a preconceived plan. (13) Heuristic power and factual novelty: [T]he criterion of 'heuristic power' strongly depends on how we construe 'factual novelty'. Until now we have assumed that it is immediately ascertainable whether a new theory predicts a novel fact or not. But the novelty of a factual proposition can 493723914 5/7 frequently be seen only after a long period has elapsed.8 (p. 69) 4. Progressive and degenerating research programmes The notion of problem shift is introduced by Lakatos 1970 and also the Lakatos' 1973 lectures included in Lakatos and Feyerabend 1999 as a "new historigraphical notion" (and also "as a sort of explication of Popper's ideas." (Lakatos and Feyerabend 1999: 101) A problem shift refers to "a series of scientific theories which replace each other with the passing of time." 9 A problem shift is said to be "theoretically progressive if each [theory] H in a sequence H1, H2, ... , Hn predicts everything that the preceding hypothesis predicted and [predicted] something in addition." It is said to be "empirically progressive if at least some of the predictions [made by each H in the sequence, judging from Lakatos 1978: 34] are corroborated."10 My interpretation of what is meant by "regressive and content-reducing" problem shift is as follows.11 A shift from Hn to Hn+1 is "regressive and content-reducing" if Hn+1 does not predict any new facts but only eliminates anomalies. many such "shifts" is "regressive and content-reducing." A problem shift that has The addition of "an untestable auxiliary hypothesis" is also said to be "regressive." [A theory] is said to be "regressive and content-reducing" "[i]f it never predicts any new facts but only eliminates anomalies through verbal tricks." (Lakatos and Feyerabend 1999: 101) (14) [I]n a progressive research programme, theory leads to the discovery of hitherto unknown novel facts. In degenerating programmes, however, theories are 8 The emphasis is as in the original. 9 It is stated in p. 101, "The term "hypothesis shift" would have been better, but it sounds very awkward." 10 Notice that the two conditions above are both sufficient and not necessary conditions. Hence we do not know what must be satisfied in order for a problem shift to be progressive, theoretically or empirically. 11 I find the exposition on p. 101 sloppy although Lakatos is not necessarily to blame for it since what has been printed is what the editor of the volume (Matteo Motterlini) produced on the basis of the transcribed lectures by Lakatos in 1973. On the basis of the exposition on p. 101, I understand that "not progressive" is the same as "regressive and content-reducing." 493723914 6/7 fabricated only in order to accommodate known facts. (15) (p. 5) A research programme is said to be progressing as long as its theoretical growth anticipates its empirical growth, that is, as long as it keeps predicting novel facts with some success ('progressive problemshift'); it is stagnating if its theoretical growth lags behind its empirical growth, that is, as long as it gives only post hoc explanations either of chance discoveries or of facts anticipated by, and discovered in, a rival programme ('degenerating problemshift').12 5. The Hard Core (that we have followed) -It seems that the hard core in our research includes the following. --A bridging statement: If (a, b) is based on some property of the CS, it is based on some relation R that is based on the structural condition of c-command. 12 I failed to provide the page number, assuming that this is a quotation. 493723914 7/7 (The Reinhartian thesis.)