During the nineteenth century, physicists and chemists, using different linguistic modes of expression, sought to describe the world for different purposes; thus, both disciplines gradually were nudged toward demarcation and self-image identification. In the course of doing so the rich complexity of the empire of chemistry was born. The essential challenge was closely connected with analysis, synthesis, and chemical process: learning the art of watching substances change and making substances change. Pursued in theory-poor and phenomenology-rich contexts chemistry nevertheless made itself intellectually, professionally, societally, and industrially creditable and attractive. The developing links between physics and chemistry are examined in this paper from the perspective of the discipline of chemistry more specifically than from the side of physics. Chemists came to believe that essentially physics was no more than mechanics. All else belonged to the domain of chemistry.

Not before the last decades of the century were firm collaborative links and genuine reciprocity fostered between physics and chemistry, and then primarily on account of the common utility of scientific research tools. At a more fundamental level physics and chemistry, in contradistinction to all the other natural sciences, experienced partial overlap and convergence because of unique mutual reliance on the construction of systems each according to its own theoretical conceptions. Still amalgamation was unthinkable. Eventually physical chemistry was loosened from chemistry in the same way that, somewhat later, chemical physics was emancipated from physics. The intrinsic messiness of chemistry, one might suggest, tends more readily to foster Bohr's opinion that “there is no rock bottom to the study of nature,” rather than Einstein's view that “we can realistically, ultimately, put it all together.”

The paper argues that the distinction between modernism and postmodernism can be applied metaphorically to clarify the changing image of music during the late Middle Ages. The paper discusses the scientific and rational strategies that thirteenth century musical theorists applied to revise earlier musical conceptualization. It highlights the thirteenth-century innovative affiliation of music with Aristotelian physics and argues that in a very subtle and seemingly contradictory way music theorists expressed the nascent awareness, if not tacit acknowledgment, of the mundane nature of music. It argues further that in the fourteenth century the issue of representing musical-rhythmical variability by means of a suitable language shifted to the forefront of musical theory and practice. The unprecedented emphasis on musical signs and their semantic behavior as well as the demand to demystify the discourse about rhythmical concepts — so as to question the necessity of metacategories — all point to an affinity between fourteenth century musical thought and postmodern sensibilities.

My contribution will focus on a central issue of Yehuda Elkana's anthropology of knowledge — namely, the role of reflectivity in the development of knowledge. Let me therefore start with a quotation from Yehuda's paper “Experiment as a Second-Order Concept.”

Elkana's paper “Two-Tier Thinking” (1978) contains the thesis that became the foundation of all his later work. This thesis is best summarized by the author himself:

The thesis of this paper is that this distinction [between realists and relativists] is not a logical necessity but a historical situation in Western scientific culture. It is claimed here that the distinction is spurious: every problem has a realist and a relativist dimension, and the two views can be, and are actually being, held simultaneously. Once a frame of reference has been selected, in it realism prevails. With respect to selection of an appropriate framework the approach has to be relativist since there is no absolute, external-to-all framework which would fit absolute realism. (Elkana 1978, 309)

In his “A Programmatic Attempt at an Anthropology of Knowledge,” published in 1981, Yehuda Elkana briefly introduced the notions of dramatic and epic theater as metaphors for distinct and opposite conceptions of history. He elaborated more fully on this theme in a paper published in 1982 on the occasion of the Albert Einstein centenary celebration. Elkana there criticized the “myth of simplicity” surrounding Einstein, and proposed to replace a “facile holism” often attributed to Einstein with “two-tier thinking.” According to Elkana, Einstein's historical epistemology was a blend of an epic, contingent view of historical scientific change coupled with strong scientific realism.

Among those who know Yehuda's work, the term “two-tier thinking” is usually associated with a problematic relativist position (Elkana 1978). But “two-tier thinking” is not a name for a philosophical argument; it is best understood, I think, as a term designating certain conditions of knowledge: universal, or modern, or perhaps only postmodern conditions, but in any case, they are generalizations derived from anthropological and psychological observations on matters of facts. This is how things actually work in the sphere of knowledge: Western intellectuals and scientists tend to acknowledge that their truth claims and certainly their normative claims are incompatible with other claims that stem from other belief systems, frameworks of thought or genres of discourses, and there is no final, impartial instance of judgment to adjudicate between the incompatible claims and the conflicting systems. Lack of “final,” impartial judgment does not hinder people from taking their truth claims seriously and acting as realists within the world constituted by their particular belief systems — tier 1. But when they come to reflect upon it, as some of them do, sometimes, they acknowledge the context-dependence of this realism and the fact that there is no way to make good on its claim to universality; theirs, they know, is but one particular “belief system,” or “genre of discourse,” among many.

Although Cassirer's four-volume Das Erkenntnisproblem in der Philosophie und Wissenschaft der neueren Zeit has long been highly regarded as an example of historical scholarship — Cassirer was awarded the golden Kuno-Fischer Medal of the University of Heidelberg in July 1914 for the first two volumes (published 1906 and 1907) — its importance for understanding his theoretical position seems to have gone unrecognized. In the English-speaking world it is, unfortunately, only known through the fourth volume, and when this appeared in English in 1950 it met with a negative, even hostile, reception (see Passmore 1968, 315f.).

Modern thought would present only an incomplete and fragmentary picture of philosophy to us if we were to regard it as being completely disconnected from the elemental forces and sources of Greek philosophy. The corrective aspect that protects it from any such attempt at unmethodical isolation is, however, given within itself and in its own content. Its own inner progress necessarily leads it back to the principles and questions that distinguished Greek speculation, which it embodied in typical forms. The thought of the modern age proves its specificity in the fact that, notwithstanding the richness of content that it gains, it remains conscious of its relatedness to these basic logical forms and strives to return to them of its own accord. They will thus themselves appear to us of their own accord and incite us to regard their contents, if we just allow ourselves to follow the course of the investigation.