Stefano Gattei

1. Stefano Gattei METHODOLOGY FOR THE SOCIAL SCIENCES IMT Institute for Advanced Studies, Lucca 2011 stefano.gattei@imtlucca.ithttp://www.imtlucca.it/stefano.gattei

2. WHAT IS A PROBLEM? The search for new knowledge does not start from observation, but from problems – problems that arise when our expectations get contradicted by experience. In Popper’s own words, learning from experience is the very act of overthrowing a theory with the help of that experience: we learn from experience, that is, by repeatedly positing explanatory hypotheses and refuting them experimentally, thus approximating the truth by stages. The more a mind is full of expectations and knowledge, the more it is a source for new problems, offers new stimuli and is a guide for future observations.

3. An observation without a problem is epistemologically impossible – because without values, knowledge and interests of the knowing subject the world would be meaningless. Theories are hypotheses for the solution of problems. They are (conjectural) attempts at problematic questions. Attempting to solve a problem is advancing some sort of causal order, discovering some causal connection that would allow to satisfy the surprise that always accompanies an unexpected problem. With an hypothesis we try to explain what is known (the effect) by way of what is not known (its causes), appealing to a more or less complex plot of universal laws or empirical generalizations that causally link two or more facts (or groups of facts).

4. As a matter of fact, however, there are no rules to arouse new and good ideas in somebody’s mind. There is no standard way to produce hypotheses that might solve problems. In Popper’s own words, there is no logic for the discovery of new theories. By contrast, we can always criticize a theory. In science as well as in everyday life, we can test a theory by testing its consequences, so as to see whether it passes a given empirical trial. It is experience that ultimately decides the fate of a theory. If we accept this principle, we are confronted with two options: we might try to verify our theory (i.e. we try tomake our theory true), or else we try to see whether it might be false (i.e. we try to falsify it).

5. For logical reasons, we can never verify a theory: for, in order to do that, we should be able to show that its content – i.e. its consequences – match the facts. But this is impossible, since the logical consequences of any given theory are infinite in number, whereas the tests scientists can actually perform are always finite in number. Moreover, false theories might very well have true consequences. However, there is a logical asymmetry between the confirmation and the refutation of theories. No number of confirmations whatsoever, however great, can ever confirm a theory, whereas a single case can, from the logical point of view, refute it. Confirmation appeals to the fallacy of the affirmation of the consequent (a wrong modus ponens, so to say): (tc) Λc]  t Whereas refutation appeals to the modus tollens:[(tc) Λ¬c]  ¬t

6. There is only one method for all sciences, then: in Albert Einstein’s words, science seeks connections that we think exist independently from the researcher. However, there are different methodologies, or testing techniques. Methodologies are not to be confused with the procedures for solving a problem. Rather, they are the techniques employed by various scientists for the acquisition of information and the test of hypotheses. Each methodology allows for the observation and study of a given aspect of an “object”. Such an observation, however, is possible only because it is guided by an hypothesis that aims at solving a problem.

7. Therefore, techniques of inquiry are tools that may be employed within a theoretical framework. They serve the construction, the elaboration and the exploitation of information, which will gradually correct and improve – by way of a trial and error elimination process – the formulation of hypotheses for the solution of problems. Once we avoid the trap of confusing the (single) scientific method with the various methodologies, we might also avoid the false alternative between quantitative and qualitativemethods. If observation is possible since it is theory-oriented, and knowledge grows by conjectures and refutations, we might say that – by definition – research will always be qualitative. Advancing new explanatory hypotheses and testing them experimentally is not something that can be subjected to quantification.

8. This does not mean that the quantification of properties of events is not part and parcel of scientific research. Only, the option qualitative/quantitative does not take place at the level of method – but, rather, at the level of methodologies. It is when they need to define the techniques of inquiry that scientists have to choose the best available tools to acquire information and test their theories – well aware that in some fields quantification is not possible (take, for instance, Carl Menger’s proposed explanation for the rise of money, as the unintended outcome of the practice of bartering), whereas in others there are quantifiable data and non-quantifiable data (take the example of Émile Durkheim’s famous essay on suicide, in which both quantitative and qualitative elements play significant roles).

9. EXPLANATIONS Solving a problem means advancing an explanatory hypothesis of the event that happens to conflict with the expectations of the researcher. There is a model of causal explanation that has become quite standard among economists, sociologists, historians and philosophers. It is a model for causal explanation that might be applied to natural as well as social sciences. In its classic formulation, it is the so-called Popper-Hempel model, or deductive-nomological model, or else covering law model.

10. DEDUCTIVE-NOMOLOGICAL MODEL(Popper-Hempel model, covering law model) Any event (explanandum) is explained when the statement that describes it can be deduced from an hypothetical apparatus (explanans) composed by singular statements (or causes) describing initial conditions, and universal statements (relevant covering laws) establishing a cause-effect link between initial conditions and explanandum. initial conditions / causes(singular statements) C1, C2, … Ck explanans covering laws(universal statements) L1, L2, … Ln logical deduction explanandum event E

11. We (causally) explain the event E when we refer it to its causes (or initial conditions, Ck) through the help of relevant general laws (Ln). C1, C2, … Ck L1, L2, … Ln E In Popper’s own words: “To give a causal explanation of an event means to deduce a statement which describes it, using as premises of the deduction one or more universal laws, together with certain singular statements, the initial conditions” (The Logic of Scientific Discovery, §12, p. 59). Laws represent logical necessity, for it would be otherwise impossible to select – out of the infinite number of facts – those deemed causally relevant and able to account for the explanandum.

12. Let us consider the following example (Popper): We have given a causal explanation of the breaking of a certain piece of thread if we have found that the thread has a tensile strength of 1kg and that a weight of 2kgs was put on it. This kind of explanation follows the D-N model: the explanandum = the breaking of the piece of thread is referred to a few initial conditions, or causes, expressed by two singular statements: C1 = “The weight characteristic for this thread is 1kg”C2 = “The weight put on this thread was of 2kgs” on the grounds of a (relevant) law described by a universal law (or hypothesis): L = “Whenever a thread is loaded with a weight exceeding that which characterizes the tensile strength of the thread, then it will break”

13. The initial conditions describe what is usually called the cause of the event in question: the fact that a load of 2kgs was put on a thread with a tensile strength of 1kg was the cause of its breaking. The prediction describes what is usually called the effect: the breaking of the thread was the effect of putting on it a weight exceeding its tensile strength.

14. SKETCHES of explanations Being a model, the covering law or D-N model is not a detailed account of scientific explanations. Its aim, in other words, is not that of providing the explanatory procedure actually followed by scientists. Rather, it confines itself to pointing out the logical model (or logical structure) of the explanation, so that we are allowed to rationally reconstruct the explanations advanced. In fact, most of the scientific explanations advanced by scientists in either the natural or the social sciences, are actually sketches of explanations, which often leave laws and/or initial conditions as “incomplete”, or “largely indeterminate”. In so doing, such hypotheses only partially account for the explanandum.

15. In many cases these hypotheses merely provide simple – but fundamental – “working hypotheses”, which highlight the structure of the explanation, somehow suggesting the direction to follow in order to achieve their rational reconstruction. In Hempel’s own words, such sketches of explanations indicate “that there is a treasure hidden somewhere. Its significance and utility will increase as the location of the treasure is more narrowly circumscribed, as the relevant conditions and the corresponding covering laws are made increasingly explicit” (Aspects of Scientific Explanation, p. 349). They are incomplete explanations – but this does not mean that they lack of laws or causes, but simply that part of the laws or part of the causes have not been made explicit, yet, or remain tacit.

16. For what concerns the effectiveness of the explanation, the economy of the theory and its understanding by a given audience, scientists believe it is useless to highlight, in a detailed and systematic way, all elements implied by the explanation – assuming that what is implicit in it can be understood all the same, given the background knowledge shared by the audience. To refer to Popper’s example, in the explanation for the breaking of a piece of thread upon which a weight exceeding its tensile strength was put, the general laws, however logically essential, are not explicitly stated. And whereas the initial conditions deemed causally relevant are explicitly mentioned, they might be further specified or clarified – we might provide, for instance, a definition of the tensile strength characterizing a specific thread.

17. CONDITIONS of adequacy In order for an explanation following the logical pattern described by the D-N model to be scientific, it must abide a number of “empirical” or “logical” principles. EMPIRICAL CONDITIONS a) the proposition describing the explanandum must be well confirmed: we cannot explain something which does not exist; b) the singular statements that describe the initial conditions must have an empirical content and be falsifiable: we cannot accept an explanation that presented as causes events that do not exist; c) universal statements describing laws must be empirically tested as well: if they are not testable, they represent mere interpretations (either philosophical, theological, ideological, etc.), not scientific theories proper. The falsifiable character of laws is a key feature of any scientific explanation.

18. LOGICAL CONDITIONS a) “the explanandum must be a logical consequence of the explanans; in other words, the explanandum must be logically deducible from the information contained in the explanans; for otherwise, the explanans would not constitute adequate grounds for the explanandum” (Hempel, Aspects of Scientific Explanation, p. 245): from: [explanans] if a piece of thread has a tensile strength of 1kg (C1) and a weight of 2kgs is put on it (C2), given the law L = “A thread breaks each time it is loaded with a weight exceeding its tensile strength” logically follows that [explanandum] “the thread breaks”.

19. b) “the explanans must contain general laws [Popper: universal laws], and these must actually be required for the derivation of the explanandum” from the initial conditions (ibidem, p. 246). This means that the laws described in the explanans must be independently testable from the phenomenon that is to be explained: grounding an explanation on a law which is only valid in the case under consideration, means advancing an ad hoc explanation. L (“Whenever a thread is loaded with a weight exceeding that which characterizes the tensile strength of the thread, then it will break”) can be deemed scientific both because it is empirically testable – being falsifiable and not yet falsified – and it is universal (it explains all instances in which the same conditions apply, and not only the single event under consideration).

20. c) the initial conditions must be distinct from the explanandum: if an explanation accounts for an event that is to be explained by referring (either directly or indirectly) to the explanandum itself, we are dealing with a circular explanation. d) the explanandum and the initial conditions must describe aspects of individual events (not individual events themselves) – aspects that were selected by researchers according to their own interests. A researcher cannot explain an event in its totality or by grasping its essence. Rather, he always inquires an event from one (or more) point(s) of view, which he deems relevant. In the above-mentioned example, we explained the breaking of a piece of thread from the physical point of view, but we might have considered it from the economical, or psychological, point of view as well.

21. TRIPARTITION OF THE SCIENCESfrom the methodological point of view The D-N model applies to all sciences: what may differ are the various applications of it the researchers might choose according to the problem-situation they are dealing with. As a consequence, we have: a) pure or theoretical science: when we look for laws of nature. Scientists contribute to the growth of scientific knowledge by discovering new laws and testing them, thus establishing new causal correlations. Once discovered, laws might be appealed to in order to explain and predict.

22. b) historical science: when we appeal to alreadyknown laws in order to explain an event that took place. In this case, scientists seek to explain what is not known (the causes) in order to explain what is known (the explanandum), by appealing to the laws available to him. In nature there are no causes and effects, but simply facts, some of which might be causally correlated only by appealing to laws: an event is explained only once it becomes the effect of one or more given causes. When doing historical science (either the astronomer explaining an eclipse, or the sociologist explaining demographic growth) scientists attempt at a historical reconstruction of the event under consideration, by encompassing only those facts – previous to the event or contemporary to it – that, given the laws then available, might be put in causal correlation with the event that is to be explained.

23. c) technological or applied science: when we set the causes and, by appealing to laws, we make predictions. In this case, scientists aim at the realization or specification of those initial conditions that their nomological knowledge (the set of laws available to them, that is) points to them as relevant in order to be able to predict a given event. If all laws are equal, the more precise is the definition of the initial conditions, the more the predictions will be reliable. An astronomer seeking to predict an eclipse; an economist trying to foresee the trend of the inflation rate; an expert in political affairs formulating hypotheses on the outcome of an election or the stability of a government – all these people are doing applied science.

24. According to individual circumstances, problem situations and other needs, scientists might orient – each time – their activity into one of these three directions. However, there are entire disciplines or research fields in which scientists are consumers, rather than producers, so to say, of the laws they appeal to. They employ, that is, laws provided by other disciplines in order to explain or predict something they are interested in. Historiography, for instance, is essentially a historical science: its task is not that of discovering (non-existent) laws for history. Rather, it applies laws and models provided by other social sciences (such as economics, social psychology, demography, etc.), as well as by common sense, in order to explain past events. The tripartition of sciences on methodological grounds, however, has the sole aim of distinguishing the various operations scientists perform, from the conceptual point of view. It does not aim at introducing any hierarchical order, of any kind.