The main message of this volume is that the creative process of discovery is not a purely rational enterprise in the traditional sense which equates rationality with logical reasoning, yet it is a manifestation of a universal phenomenon ...

In this paper, I try to decipher the role of internal symmetries in the ontological maze of particle physics. The relationship between internal symmetries and laws of nature is discussed within the framework of “Platonic realism.” The notion of physical “structure” is introduced as representing a deeper ontological layer behind the observable world. I argue that an internal symmetry is a structure encompassing laws of nature. The application of internal symmetry groups to particle physics came about in two revolutionary steps. (...) The first was the introduction of the internal symmetries of hadrons in the early 1960s. These global and approximate symmetries served as means of bypassing the dynamics. I argue that the realist could interpret these symmetries as ontologically prior to the hadrons. The second step was the gauge revolution in the 1970s, where symmetries became local and exact and were integrated with the dynamics. I argue that the symmetries of the second generation are fundamental in the following two respects: According to the so-called “gauge argument,” gauge symmetry dictates the existence of gauge bosons, which determine the nature of the forces. This view, which has been recently criticized by some philosophers, is widely accepted in particle physics at least as a heuristic principle. In view of grand unified theories, the new symmetries can be interpreted as ontologically prior to baryon matter. (shrink)

According to structural realism, in mature science there is structural continuity along theoretical change. A major counterexample to this thesis is the transition from the Eightfold Way to the Standard Model in particle physics. Nevertheless, the notion of structure is significantly important in comprehending the theoretical picture of particle physics, where particles change and undergo transmutations, while the only thing which remains unchanged is the basic structure, i.e. the symmetry group which controls the transmutations. This kind of view agrees with (...) the paradigmatic case where the structure is an internal symmetry and the instantiations are the elementary particles. The metaphysical view which reflects this situation is a version of ontic structuralism. (shrink)

Fundamentismus und Skeptizismus-Anarchismus sind zwei entgegengesetzte Positionen in der traditionellen Erkenntnistheorie und in der modernen Wissenschaftstheorie. Zwischen ihnen gibt es einen dritten Standpunkt, den Evolutionismus. Beispiele sind zwei neuere Arbeiten von Putnam und Stegmüller . Im Gegensatz zum logisch-statischen Fundamentismus berücksichtigt der Evolutionismus auch dynamische und naturalistische Ansätze. Stegmüller folgend entlehnen wir in der vorliegenden Untersuchung aus der Sprachphilosophie pragmatische Gesichtspunkte, um die logische Syntax und Semantik, die Werkzeuge des Fundamentismus, zu ersetzen. Wir zeigen die Kraft der Pragmatik bei der (...) Behandlung von Problemen wie Erkenntniswachstum, Begriffswechsel, Theorien- und Bedeutungsdynamik, wissenschaftliche Entdeckung und besonders beim Problem der Inkommensurabilität. Unser nicht-fundamentistischer Vorschlag ist ein heuristisches Modell, das auf der modernen genetischen Theorie basiert. (shrink)

The paper investigates the implications of a nonaprioristic philosophy of science. It starts by developing a scheme of justification which draws its norms from the prevailing paradigm of rationality, which need not be universal or external. If the requirement for normativity is then abandoned we do not end up with a descriptive philosophy of science. The alternative to a prescriptive philosophy of science is a theoretical explanation of scientific decisions and acts. Explanation, rather than mere description, replaces justification; and the (...) paradigm of rationality becomes a scientific paradigm. The implications of these results for the discovery-justification distinction are investigated. An explanatory philosophy of science deals with the generation, as well as with the selection of scientific conjectures: both contexts have an epistemic dimension. * This paper was written under the auspices of the Wolfson Chair Extrordinary of Theoretical Physics, Tel Aviv University. (shrink)

In this paper a model is presented for the growth of knowledge in a dynamic scientific system. A system which is in some respects an idealization of a Lakatosian research program. The kinematics of the system is described in terms of two probabilistic variables, one of which is related to the evolution of its theoretical component and the other--to the growth of the empirical component. It is shown that when the empirical growth is faster than the theoretical growth the posterior (...) probability of the theoretical component increases. Thus, empirical progressiveness of a research program, as explicated in this model, is accompanied by an increase in the degree of confirmation. In such a case the system grows in a Popperian-like spirit, while learning from experience in a Bayesian manner. (shrink)

Scientific thought is characterized in general as methodical and rational. I would like to present here an opposing view which treats science as a non-systematic activity, where serendipity, tinkering and imitation, rather than so-called rational thought, characterizes it. All these kinds of acts, which are considered to be a-rational, are related to an evolutionary view of science. I will deal here with a version of evolutionary epistemology as applied to science, integrated with the concept uf "meme". Richard Dawkins, who coined (...) the term "meme", treats memes as units of information which propagate in the meme-pool by leaping from brain to brain. The way that memes replicate is through imitation. Examples for this phenomenon in science are illustrated by some historical cases. In particular, I will deal with the evolution of theories of "internal symmetries" in particle physics. Memetics is the counterpart of genetics in the cultural arena. In its application to science, it deals with the manner memes/ideas spread in scientific communities. (shrink)

Scientific thought is generally characterized as methodical and rational. I would like to present here an opposing view which treats science as a non-systematic activity, where serendipity, tinkering and imitation, rather than so-called rational thought, characterizes it. All these kinds of acts, which are considered to be a-rational, are related to an evolutionary view of science. I will deal here with a version of evolutionary epistemology as applied to science. The combination of variation and competition for survival is analogous to (...) the elements of Darwinian evolution. I will give some examples for this phenomenon in science from historical cases and Examples for this phenomenon in science are illustrated by some historical cases, in particular by the evolution of theories of internal symmetries in particle physics. (shrink)

In modern physics the notion of structure can be treated as an extension of the notion of law of nature. French and Ladyman’s view concerning the ontological priority of structures over objects is confronted with Psillos’ criticism. This kind of view agrees with the paradigmatic case where the structure is an internal symmetry and the instantiations are elementary particles. An ontological model is proposed which demonstrates the relation between structures and their instantiations in this case. This view which may be (...) categorized as “weak ontic structuralism” is compared with Busch’s treatment of ontic structuralism in the philosophy of mathematics. (shrink)

An attempt is made to give a methodological and physical characterization to the concept of the structure of matter. The methodological status of theories describing the structure of hadrons is discussed. A parallelism is drawn between the quark model as a theory of the mathematical composite structure of hadrons and Plato's theory of matter. The merger of the bootstrap idea with a quark substructure of hadrons is discussed. A third approach to the structure of hadron matter is presented. It resembles (...) the Aristotelian conception of primary matter on which form is imprinted potentially. (shrink)