Forskningsprojekt Icke-empirisk teorikonfirmering i fundamental fysik
Analysen av icke-empirisk konfirmering har hittills applicerats på strängteori, då denna utgör ett praktexempel på en betrodd teori som saknar empiriskt stöd. Det föreliggande projektet avser att applicera begreppet på en vidare klass av fysikteorier, där teorin har något empiriskt stöd men inte är slutgiltigt bekräftad.
Den fundamentala fysiken befinner sig idag i en intressant men märkvärdig situation. Samtidigt som betydande steg mot en universell begreppslig förståelse av fysiska fenomen tagits under de senaste årtiondena, har det blivit allt svårare att uppnå empiriskt stöd för de motsvarande teorierna. De karakteristiska förutsägelser som görs inom kosmologisk inflationsteori, strängteori och ett antal teorier inom högenergifysik ligger delvis eller fullständigt bortom alla möjliga experiment. Trots detta hyser förespråkare av till exempel inflationsteori och strängteori en stark tilltro till dessa teorier.
Den allmänt erkända förståelsen av teorikonfirmering vilar på en dikotomi mellan teorier som har stöd från empirisk evidens å ena sidan, och obekräftade spekulationer å den andra. Det är inte på en sådan grund möjligt att redogöra för den starka tillit fysiker har inför vissa empiriskt obekräftade teorier.
Jag har i en nyligen utkommen bok, "String Theory and the Scientific Method", pläderat för en utvidgning av
teorikonfirmeringsbegreppet. Jag inför där vad jag kallar "icke-empirisk konfirmering". Denna grundas i observationer som inte kan sägas utgöra empirisk evidens för en given teori, eftersom de inte är förutsägelser härledbara från teorin. Observationen att inget alternativ till en viss teori har hittats, eller att betrodda teorier inom forskningsfältet som saknat empiriskt stöd historiskt har tenderat att få sådant stöd när de väl gjorts testbara, räknas till exemplen. Jag hävdar att, genom att inkludera icke-empirisk konfirmering kan vi uppnå en mer adekvat förståelse av faktisk teoribedömning inom samtida fundamental fysik.
Analysen av icke-empirisk konfirmering har hittills fokuserats på strängteori, då denna utgör ett praktexempel på en betrodd teori som saknar empiriskt stöd. Det föreliggande projektet avser att applicera begreppet på en vidare klass av fysikteorier, där teorin har något empiriskt stöd men inte är slutgiltigt bekräftad. Att utvidga analysen i denna riktning är viktigt för att belysa relevansen hos icke-empirisk konfirmering i allmänhet, och hur empirisk och icke-empirisk konfirmering relaterar till varandra.
Två fysiksammanhang kommer att beaktas. Det första fallet är samtida kosmologi med fokus på inflationsteori. För detta fall finns stora mängder empirisk data, men slutgiltig teoribekräftelse är svår att uppnå av flera skäl. Målet är att visa att icke-empiriska konfirmationsstrategier spelar en avgörande roll för att bestämma statusen hos teorier i samtida kosmologi. Vi betraktar här i detalj hur empirisk och icke-empirisk konfirmation samverkar. En viktig fråga är statusen hos så kallade naturlighetsargument inom kosmologin, och hur dessa är relaterade till icke-empirisk konfirmering.
I det andra fallet vänder vi oss till atomismteori från förra sekelskiftet, när denna gick från att vara en produktiv men empiriskt obekräftad hypotes till en teori med stöd av empiri. Vi undersöker i detalj vilka typer av ickeempirisk konfirmering som kan identifieras under denna process.
Utöver dessa undersökningar av specifika fysikteorier kommer vi i en andra del av projektet avse att klargöra den generella strukturen hos icke-empirisk teorikonfirmering. Detta sker inom ramarna för formell bayesiansk konfirmationsteori.
Projektet har som mål att forma en förståelse av teoribedömning och teorikonfirmering, sådan att den kan redogöra för hur forskare faktiskt resonerar inom samtida fundamental fysik. Om det är framgångsrikt kan det bidra signifikant till en adekvat tolkning av statusen hos fysikteorier i det tjugoförsta århundradet.
Projektbeskrivning
Research Plan
Non-Empirical Theory Confirmation in Fundamental Physics
Purpose and Aims
The project aims at developing a general understanding of the role of non-empirical theory confirmation in physics. The hypothesis shall be put forward and tested that non-empirical theory confirmation plays a structurally important role in scientific reasoning. Non-empirical evidence extends the body of evidence that is relevant for theory confirmation. This makes theory confirmation possible even in scientific contexts where no empirical evidence is available. More generally, however, it modifies the understanding of the overall process of theory confirmation also in contexts where confirming empirical data has been gathered. An adequate appraisal of non-empirical theory confirmation may be expected to
contribute to a better understandin g of the scientific process and to provide a new perspective on a number of long-standing problems in the philosophy of science. It will also be important, however, to investigate the limitations of non-empirical theory confirmation and the risks and problems associated with its increasing role in contemporary physics. Overextending its range may lead to serious repercussions for the scientific process.
The project will deploy a two-tiered strategy. Specific investigations of contemporary cosmology and late 19th/early 20th century atomism shall provide a better understanding of nonempirical confirmation in past and present physics. A general conceptual analysis, relying on Bayesian confirmation theory, shall clarify general structural aspects of the approach.
Survey of the field
The concept of non-empirical theory confirmation may be best explained in a Bayesian framework by comparing it with empirical confirmation. A scientific theory makes predictions about a certain class of phenomena. This class of phenomena is called the intended domain of the theory. Empirical testing of the theory consists in gathering data that may either agree with or differ from the theory’s predictions. Agreement of the data with the theory’s predictions
increases the probability of the theory and thereby, in a Bayesian sense, constitutes empirical confirmation. “Non-empirical confirmation” of a theory, to the contrary, denotes an increase of the theory’s probability due to observations that lie beyond the theory’s intended domain. It does not rely on the agreement between empirical data and the theory’s predictions. For example, one may trust a theory because it is the only explanation of a given phenomenon one can think of. (We call this argument the no alternatives argument.) Another reason can be the observation that,
within a given research field, the core predictions of a theory usually get confirmed by empirical testing if no alternatives to that theory have been found. (We call this argument the metainductive argument from scientific success.) It is clear that neither of these observations can be predicted by the corresponding scientific theory. Nevertheless, they can play an important role in assessing that theory’s chances of being viable. In the recent book “String theory and the Scientific Method” (Dawid 2013), the author makes the case that non-empirical theory confirmation plays a crucial role in string theory and related research contexts: on the one hand, the lack of empirical confirmation generates a special need for non-empirical theory confirmation in those cases; on the other hand, the particularly powerful role of consistency arguments (i.e. inferences from the requirement of consistency to specific properties of the theory) makes purely theoretical reasoning very effective.
It is further argued that non-empirical theory confirmation typically relies on assessments of the underdetermination of scientific theory building. Underdetermination of scientific theory building by the available data (in short ‘scientific underdetermination’) denotes the spectrum of scientific theories that are empirically distinguishable (by some set of future experiments) and can be built in agreement with the available data. If scientific underdetermination is strongly
limited, that is if the number of possible scientific alternatives is small, this enhances the chances of future predictive success of a specific theory that is consistent with the currently available data. Trust in string theory is based on the assessment that scientific underdetermination is very severely limited in the given research context.
The role and significance of non-empirical theory confirmation had not been sufficiently appreciated in philosophy of science until recently. While it had always been acknowledged that scientists deploy non-empirical strategies of theory assessment, those assessments were mostly taken to constitute mere heuristics which played a subjective role for individual scientists trying to make up their mind whether or not they should invest time and energy in working on a given theory. They were not understood, however, to amount to a reliable and epistemically viable element of scientific reasoning. Recent developments in fundamental physics and an improved understanding of the mechanisms involved in that kind of reasoning (see Dawid, Hartmann and Sprenger 2015, Dawid 2006, 2009, 2016, 2017) suggest a different perspective that acknowledges non-empirical theory assessment as a viable form of theory confirmation.
The investigation of non-empirical confirmation stands in the tradition of ideas advocating a broadening of the understanding of theory assessment that reaches back to Laudan’s discussion of conceptual problems in science (Laudan 1977). It relies on a notion of “scientific” or “transient” underdetermination that has been introduced and analysed in Sklar (1975, 2000) and Stanford (2001, 2006). Features of non-empirical confirmation can be analysed
in an instructive way within a Bayesian framework (see e.g. Howson and Urbach 2006 and Bovens and Hartmann 2003).
The concept of non-empirical confirmation has been discussed in recent years in a number of reviews (e.g. Ellis 2013, Huggett 2014, Smolin 2014, Rickles 2016, Vistarini 2014, Schindler 2016), and analysed and applied in commentaries and articles (e.g. Crease 2014, Ellis and Silk 2014, Herzberg 2014, Camilleri and Ritson 2015, Peebles 2016, Rovelli 2016). These discussions raise a number of specific issues that will be addressed in the project work. In particular, the project work is expected to clarify questions related to the stability and significance of non-empirical confirmation in actual physics.
The layout of the project
The project will be pursued at two different levels. Two case studies will investigate in detail the specific mechanisms of non-empirical theory assessment and theory confirmation in physics. The first study chooses a historical perspective. By analysing the role of non-empirical theory assessment in late 19th and early 20th century physics, it will aim at identifying lines of continuity that lead from that period to the current situation. The second study will address the
situation of contemporary cosmology, where non-empirical confirmation plays a particularly important and complex role. At a general conceptual level, the structure of non-empirical theory confirmation shall be analysed and the wider philosophical relevance of this approach shall be discussed.
I: Physical Case Studies:
Non-empirical theory assessment plays a particularly conspicuous role in fundamental physics. A number of reasons can be given for this fact. First, the rigidly mathematical nature of physical analysis implies that consistency arguments play a very important role in theory building. The use of consistency arguments allow for a higher degree of independence of the process of theory building from empirical data. Second, the abstract nature of scientific objects in
fundamental physics in conjunction with their complex and multi-layered connection to experimental testing requires assessments of limitations to scientific underdetermination in order to establish the empirical discovery of those objects (see Dawid 2013, 2009). Finally, the influential position of empirically unconfirmed theories in contemporary fundamental physics turns non-empirical theory assessment into a constitutive element of today’s physical world view. Two different contexts of physical research shall be investigated in detail in order to gain a comprehensive understanding of the role of non-empirical theory assessment in the field.
a) Atomic theory and ether theory in the late 19th and early 20th: The atom was generally acknowledged to have found conclusive empirical confirmation after Perrin’s experiments of 1908 to 1911. The process of conceptual evolution and empirical testing that led up to this development (see e.g. Chalmers 2009, Clark 1976, Needham 2004), is of particular interest with respect to the intricate role of non-empirical theory assessment. In the 19th century, the
understanding was prevalent that genuine empirical confirmation could only be achieved for hypotheses about observable objects. The atom-hypothesis therefore was understood to be a potentially scientifically productive but not empirically testable conjecture. This understanding changed gradually with the improvement of experimental techniques and the increase of the specificity of hypotheses on non-observable objects. An extensive discussion in the philosophy of science has been devoted to the philosophical interpretation of the step towards the empirical
confirmation of the atom. (see e.g. Achinstein 2001, Roush 2006, Stanford 2006). It is a matter of debate what exactly constituted the crucial element for acknowledging Perrin’s experiments as a conclusive empirical test of atomism. While some philosophers emphasize the coherence of different experiments (Achinstein 2001), others (Roush 2006) focus on the deductive aspects of the relation between the core claim of atomism and one specific experiment. It was suggested in (Dawid 2013) that the assessment of limitations to scientific underdetermination can be a helpful concept for attaining a better understanding of this question. On that account, the step towards acknowledging the empirical confirmation of the atom goes along with an integration of a certain level of assessment of underdetermination into the concept of empirical confirmation of an unobservable object. This move turns assessments of underdetermination into an implicit element of the concept of empirical confirmation and thus constitutes a significant change of that concept. It is planned to carry out a more extensive analysis of the history of atomism in the 19th and early 20th century from the described perspective in order to test the stated claims. Of particular interest in this context are ideas emphasising the significance of non-empirical theory assessments that were discussed by J. C. Maxwell (Achinstein 2010).
The success of atomism can be contrasted with the history of the ether. The existence of the ether was for a long time believed to be well established based on a no-alternatives argument. While the ether itself had not been observed, a wide range of empirical data that confirmed the wave theory of light was taken to provide indirect evidence for the ether. This assessment was based on the understanding that a satisfactory wave theory of light could not be constructed without assuming the ether. The eventual demise of ether theories due to the success of special relativity can be seen as one of the most conspicuous examples of a failure of a no-alternatives argument in modern physics. A comparison between atomism and ether theory may contribute to a better understanding of the risks of non-empirical theory confirmation. What are the conceptual differences between the straightforward application of a no-alternatives argument in the ether case and the more complicated and implicit role of non-empirical theory assessment in the case
of atomism? Can those conceptual differences be related to the eventual failure of non-empirical theory assessment in the ether case? Or must the ether case be read as a general warning against endorsing non-empirical theory confirmation in the absence of direct empirical confirmation?
In a second stage of the investigation those questions shall be addressed.
b) Modern cosmology: Cosmology today constitutes a particularly interesting context for investigating the role and significance of non-empirical theory confirmation. Inflationary cosmology (see e.g. Linde 2008), the prevalent ‘paradigm’ in the field in recent years, is based on the idea that the current phase of universe expansion was preceded by a phase of exponential expansion. This idea is deployed in order to explain observed core characteristics of the universe such as the high degree of isotropy, homogeneity and flatness of space. Consistency and naturalness arguments then lead from this basic conjecture to the conception of eternal inflation. This conception posits a multiverse structure where individual universes are generated due to quantum fluctuations in a background space that eternally remains in an exponentially expanding phase.
Cosmic inflation today is supported by quantitative empirical evidence. Technological progress provides a steadily improving base of empirical data in cosmology. Measurements of red-shifts of distant supernovae allow conclusions regarding the cosmological constant. Precision measurements of background radiation can be interpreted in terms of the size of quantum fluctuations. New and increasingly precise measurements of cosmic background radiation in
particular, (WMAP, PLANCK, BICEP) provide non-trivial empirical tests of models of cosmic inflation. Their agreement with the predictions of simple or “natural” models of cosmic inflation amounts to a significant element of empirical corroboration of inflation. Still, the data is not understood to constitute conclusive empirical confirmation of cosmic inflation for two reasons.
First, cosmic inflation per se does not predict precise specific values with respect to thenmeasured parameters. A large range of values may be provided by the full spectrum of models. The more ‘unnatural’ or fine-tuned models one is ready to accept, the larger gets the range of possible parameter values. Evaluating the significance of the empirical data therefore is closely related to assessing the difficult role of naturalness in physics. The project will address those issues and discuss in how far they appear in a different light once non-empirical confirmation is taken into account.
Second, it seems difficult to disregard unconceived alternative reasons for the observed data patterns. In other words, assessments of limitations to scientific underdetermination seem particularly difficult to attain but play an essential role in evaluating the implications of empirical data. While empirical evidence does contribute considerably to theory evaluation in present cosmology, the lack of conclusive empirical confirmation thus gives an important and irreducible
role to non-empirical strategies of theory assessment as well. In this light, cosmic inflation constitutes a particularly interesting scenario where theoretical elements of theory assessment are strong but, unlike in the case of string theory, merge with empirical arguments to bring about an overall assessment of a theory’s status.
It is planned to carry out a thorough analysis of this specific situation and discuss mechanisms, perspectives and problems of the involved strategies of reasoning. This investigation is of interest beyond the range of cosmological theory building for the following reason. The classical strategy of testing particle physics theories in large collider
experiments cannot be expected to remain feasible far beyond the energy levels reached at the LHC today. While some steps of improvement or even one more big experiment are thought about by collider physicists, it is generally considered realistic to expect that cosmological data will constitute the main source of empirical data for evaluating the theories of particle physics and string theory in the future. In this sense, looking at the situation of cosmology may be taken to address future options for empirical evaluations of high energy physics as well.
II: The general form and philosophical significance of non-empirical theory confirmation:
Reaching out beyond the individual exemplifications of non-empirical confirmation in specific
case studies, the project aims at acquiring a general understanding of the role played by nonempirical
theory confirmation in the scientific process. To that end, three main questions will be
addressed: what is the precise argumentative structure of non-empirical theory confirmation?
Can non-empirical theory confirmation be related to other epistemological concepts in the
philosophy of science? What are the general philosophical implications of the rising importance
of non-empirical theory confirmation? Each of these questions will be the subject of one
investigation.
a) The completion of a formal reconstruction of non-empirical theory confirmation: In
order to attain a better understanding of the argumentative structure of non-empirical theory
confirmation, it is very helpful to find a formal reconstruction of those arguments. Three main
arguments of non-empirical theory confirmation have been distinguished in Dawid (2006, 2013).
One of them, the no alternatives argument, has already been formally reconstructed in a Bayesian
framework in (Dawid, Hartmann and Sprenger 2015). The no alternatives argument is based on
the observation F that scientists have not found any alternatives to theory H. F does not
constitute empirical evidence for H since it is not predicted by H. It is demonstrated in the paper
that, under plausible conditions, F indeed constitutes confirmation of H and therefore exemplifies
non-empirical theory confirmation. The basic idea of the analysis is to introduce a statement Y
on the number of possible alternative theories to a given theory H. It is then shown that, given
that certain plausible conditions are fulfilled, F increases the probability of H being true or viable
by increasing the probability of the truth of statements asserting smaller numbers of possible
alternatives. The project will extend this analysis to the other two main arguments of nonempirical
theory confirmation.
Of primary importance is the meta-inductive argument from scientific success (see
Introduction). This argument is essential for understanding the significance of non-empirical
theory confirmation in general. Though the no alternatives argument can be shown to establish
non-empirical confirmation, on its own grounds nothing can be said about the significance of
that kind of confirmation. In principle, the confirmation value of the fact that no alternatives
have been found could be irrelevantly small. In order to assess the significance of the no
alternatives argument, the argument’s relevance must be “gauged” by looking at the historical
record of its success. This can be done based on the meta-inductive argument from scientific
success. The latter therefore plays a double role as a strategy of generating non-empirical
confirmation in its own right and as an indicator of the significance of other arguments like the
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argument of no alternatives. The project will aim at a complete formal reconstruction of this
argument.
The third argument, the argument from unexpected explanatory interconnections,
resembles a theoretical equivalent to the argument of novel confirmation. In the novel
confirmation case, the idea is that a theory’s agreement with data that had not entered the
theory’s construction process has higher confirmation value than agreement with data the theory
was built to reproduce. In a similar vein, it can be argued that explanations or conceptual
interconnections a theory delivers without having been built to that end have some confirmation
value for that theory.
In conjunction, a successful formal reconstruction of the three presented arguments could
constitute a convincing formal support of the relevance and significance of non-empirical theory
confirmation.
b) Comparing non-empirical theory confirmation with a formal account of inference to the
best explanation (IBE): IBE is a mode of inferring a theory’s truth or viability from the fact that
it is the best known explanation of the collected data. IBE is related to non-empirical theory
confirmation in a complex way that deserves close analysis.
At a general structural level, the two concepts are entangled. IBE must rely on the
understanding that the set of theories known at the present stage contains a true or viable
explanation of the phenomenon in question. If the true theory were not contained in the set of
known theories, the best known explanation would still be false. Therefore, IBE implicitly
involves the question of the number of all possible alternative theories that is the core issue of
non-empirical theory confirmation. Conversely, a careful look at non-empirical theory
confirmation also reveals elements of IBE: a reconstruction of non-empirical theory confirmation
on the basis of limitations to underdetermination is based on the understanding that such
limitations are the best explanation of the observations which are considered non-empirical
confirmation of given scientific theory. Therefore, IBE plays a role in non-empirical
confirmation at a meta-level.
Despite these conceptual interconnections, IBE typically seems to address different
scientific contexts than non-empirical theory confirmation. IBE is normally applied in cases
where empirical confirmation of core predictions of the theory in question has already been
achieved. In those cases, empirical confirmation is considered a precondition for calling a theory
a good explanation. Second, IBE is mostly applied in contexts where more than one scientific
explanation is available. Therefore, one core argument of non-empirical confirmation, the no
alternatives argument, does not apply. (Bird 2007 deals with the specific case of ‘inference to the
only explanation’, however.) IBE and non-empirical theory confirmation thus focus on opposite
ends of the spectrum of scientific reasoning. Non-empirical theory confirmation is strongest in
fundamental physics where theory building is highly constrained and empirical confirmation is
very difficult to attain. IBE is best applicable to situations in the special sciences where a
spectrum of theories is available and can be compared based on their agreement with empirical
data.
Nevertheless, the aforementioned conceptual connections between the two approaches in
conjunction with the previously discussed indications that non-empirical theory confirmation is
of general importance for understanding the scientific process suggest that the two approaches
may best be understood as complementary perspectives which are both required for a full
understanding of theory assessment. In this light, it is planned to carry out an analysis of the
conceptual interconnections between non-empirical theory confirmation and IBE.
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Lipton (2004) argues that IBE should be deployed for specifying the prior probabilities
deployed in a Bayesian context and therefore is not just compatible with but an integral part of
Bayesian reasoning. The line of reasoning sketched in this subsection suggests a different
connection between IBE and Bayesian reasoning: by providing information about the spectrum
of possible alternative theories, non-empirical evidence generates the basis for developing a
convincing form of IBE. IBE in this light appears as a form of inference whose inductive base is
located at level of non-empirical evidence. The project will aim to carry out a full analysis of the
connection between IBE and non-empirical confirmations based on this idea.
c) Formulation of a position in the scientific realism debate that accounts for a more
important role of non-empirical theory confirmation: The scientific realism debate is one of
the most widely discussed topics in the philosophy of science. A modern empiricist position has
been defined and developed in recent decades by van Fraassen (1980, 2006). An influential form
of scientific realism that is of particular interest from the perspective on non-empirical theory
confirmation is structural realism. It was first presented as by John Worrall (1989) and later
formulated in its ontic version by James Ladyman (1998) and others.
Taking non-empirical theory confirmation into account can open up new perspectives on
the scientific realism debate based on the following general line of reasoning: the significance of
non-empirical theory confirmation indicates limitations to scientific underdetermination; this
structural feature of scientific reasoning then in turn can have an impact on the question of
scientific realism. Three specific ways in which this line of reasoning can work shall be
investigated.
First, accounting for non-empirical theory confirmation can throw new light on the issue
of unconceived alternatives that was recently addressed by Kyle Stanford (Stanford 2001, 2006),
who refers to earlier work by Lawrence Sklar (Sklar 1975, 1981). Stanford argues against
scientific realism by pointing out that a claim of scientific realism must rely on the assessment of
the number of unconceived alternatives, i. e. the number of possible alternative scientific theories
that have not yet been developed. One can only be confident that the present theory is
(approximately) true if one assumes that no (fundamentally different) alternative theories can
account for the collected data as well. Stanford goes on to argue that scientists are not good at
making such assessments. He lists a number of cases where no alternatives were in sight for a
long time but eventually did occur.
The issue of unconceived alternatives is closely related to the assessment of scientific
underdetermination. If it is true that non-empirical theory confirmation i) is of importance in
many scientific contexts and ii) relies on assessments of scientific underdetermination, those two
facts in conjunction may work against Stanford’s position.
Second, acknowledging the significance of limitations to scientific underdetermination
also raises new problems for the no miracles argument for scientific realism. The no miracles
argument (Putnam 1975, Boyd 1990) asserts that the predictive success of science would be a
miracle if scientific realism were false. Limitations to scientific underdetermination, however,
can be related directly to a theory’s chances of predictive success. Since limitations to scientific
underdetermination do not per se imply scientific realism (see Dawid 2013), they therefore offer
an alternative explanation of predictive success and threaten the viability of the no miracles
argument.
Finally, limitations to scientific underdetermination may also be of interest for
developing a satisfactory form of structural realism. It has been a longstanding debate whether
and if so how structural realism, which focuses on the reality of structure rather than ontological
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objects, can be distinguished from modern forms of empiricism. Roughly, structural realism
faces the following dilemma: it seems that, in order not to fall back on empiricism, structural
realism must be capable of distinguishing different scientific theories based on criteria that are
not fully empiricist; however, at the same time structural realism must avoid building those
criteria on ontological posits which would reintroduce ontological realism through the back door.
A number of critics (e.g. van Fraassen 2006, Psillos 2006) have expressed doubts whether
steering a middle path of this kind is feasible. The concept of limitations to scientific
underdetermination may offer a strategy for establishing theory individuation in a non-empiricist
way without falling back on ontological realism. Very briefly, this may work the following way.
Claims about limitations to scientific underdetermination rely on scientificality conditions which
define the realm of valid scientific theory building. At the level of phenomenal description, to the
contrary, no limitations to underdetermination can be specified. Based on this distinction
between a phenomenal and a scientific conceptual level of description, real structure may be
distinguished from an empiricist take on structure based on the assessment of the space of
possible theories at the scientific conceptual level. If sufficiently strong, limitations to scientific
underdetermination may establish the reality of a given structure by ruling out alternatives
without referring to any form of real ontology.
The project will aim at integrating the three described lines of reasoning into an overall
conception that defines a coherent position in the scientific realism debate.
The project will be carried out by Richard Dawid as the principal researcher and Casey
McCoy as Postdoc. The Bayesian formalization of non-empirical confirmation will be worked
out in cooperation between Richard Dawid, Stephan Hartmann at the LMU Munich and Jan
Sprenger at the University of Tilburg. All other project topics will be worked on in collaboration
by the two project researchers. The project work will result in a number of scientific articles to
be be submitted to leading journals in the philosophy of science. It is planned to hold a workshop
with about 12 participants on the philosophy of cosmology in the second project year and
another slightly larger one non-empirical confirmation and related topics in the fourth year. The
first project year will be devoted to cosmology. The second one will be spent on the issue of
atomism. The second half of the project time will then be devoted to IBE and scientific realism.
The Bayesian formalization of non-empirical confirmation is planned to be carried out in parallel
during the first two project years.
International Cooperation
There will be an international cooperation with Stephan Hartmann at the LMU Munich and Jan
Sprenger at the University of Tilburg on the Bayesian formalization of arguments of nonempirical
confirmation.
Significance
The scarcity of empirical data that can test contemporary theories of fundamental physics is one
of the most substantial problems physics faces today. The investigation of non-empirical
confirmation addresses this problem and aims at providing a very general approach to theory
assessment that can serve as a basis for understanding the epistemic status of theories in
fundamental physics in upcoming decades. In this vein, it has attracted considerable interest in
recent years in physics and the philosophy of science. Indicative of that interest are the highly
visible and publicized interdisciplinary workshop on confirmation in contemporary fundamental
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physics organized by Richard Dawid in Munich in 2015 and Richard Dawid’s opening plenary
talk at the conference “Foundations 2016” in London on this topic.
Preliminary results
As indicateded above, Richard Dawid has developed the concept of non-empirical confirmation
in the context of string theory and has analyzed some of its aspects in a general context within a
Bayesian framework. Dawid 2006, 2007, 2009, 2013, 2016, 2017 and Dawid, Hartmann and
Sprenger 2015 have provided results on which the present project can build. Casey McCoy has
worked extensively on the philosophy of cosmology, with a particular focus on its statistical
aspects (McCoy 2015, 2017, 2017a), which will play an important role in the project.
References
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Bird, A. 2007: ‘Inference to the Only Explanation’, Phil. & Phen. Research 74, 424-432.
Bovens, L. and S. Hartmann 2003: Bayesian Epistemology, Oxford: Oxford University Press.
Camilleri, K. and Ritson, S. 2015: “The Role of Heuristic Appraisal in Conflicting Assessments
of String Theory”, Studies in History and Philosophy of Modern Physics 51: 44-56.
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