Taking the History of Science Really Seriously (eBook)

Chapter I.1

Kuhn I: The Copernican Revolution (1959)

A historiography of science should embody a criterion for demarcating science from non-science through a historical timeline. The timeline represents a history of one or more converging or diverging scientific disciplines. The timeline contains a succession of episodes and various cognitive, ontological and methodological commitments. One such historiography, subscribed to more by scientists than historians, chronicles and describes the most recently successful scientific enterprises but dismisses all or most seemingly contrary predecessors as unscientific, called ‘Whiggism’ (Butterfield, 1931), or, more descriptively, chauvinism of the present.

In the introductory essay to the Structure (1962) Kuhn notes his surprise at finding that Aristotle’s natural philosophy of the Cosmos, Earth and Planets meets most if not all requirements for scientific status. Immediate observations of these objects and their movements are cited in arguments for a two-sphere cosmos and for planetary motions. Empirical constructs such as methods for recording solar locations and motions, for identifying and re-identifying planets and stars, for setting up terrestrial and celestial coordinate systems are an essential part of the 4th century research program. An epistemic objective offered in Plato’s Republic prescribed ‘saving’ seemingly chaotic appearances (wanderings) by mathematical constructs analogous to the Pythagorean theory of harmonies.

Nevertheless, Kuhn’s sampling of the history of science is episodic and scattered among several scientific disciplines, including electricity, chemistry, relativity and classical mechanics, as well as planetary astronomy. The overall picture of the history of science offered in the Structure can be compared to punctuated equilibrium in evolutionary theory. The history of a scientific discipline is punctuated with a succession of wholly distinct scientific paradigms that endure for various bounded time intervals and are subject to empirical challenges only within their local conceptual and deontic (valuational) environment. Another historiography with an evolutionary analogy would embody Darwinian gradual and cumulative progression, tree-like branching of disciplines with some reticulation (crossing of branches), with some lineages going extinct and others conserved and supplemented, absorbed or ramified by successors. These two historiographies are not necessarily dichotomously distinct: punctuated equilibrium allows species to be linked by a succession of descendants and founders which may not be evident in the fossil record. Darwinian gradualism allows episodic and lasting innovations, founders of clades, as well as partial and wholesale deletions. In sum, the historical progression of science can be sketched as a ramifying tree with some reticulate branches. (Cf. Kuhn, 1962, XIII)

Hellenic and Hellenistic Planetary Astronomy: The Paradigm of Paradigms

On p.90 in the Structure of Scientific Revolutions (first edition, 1962) Kuhn describes paradigms as punctuating history with wholly distinct variations of several components, ontology, method and empirical access. These components are aptly illustrated in the homocentric sphere cosmology of Plato and Aristotle. It is evident, from Kuhn’s description of his ‘Aristotle experience’, that the homocentric universe was the exemplar for Kuhn’s theory of paradigms in the Structure. The overall positive heuristic (Lakatos, 1970) for planetary astronomy was formulated by Plato: replace the whole ‘wandering’ planets appearing to immediate experience with Pythagorean mathematical constructs that demonstrate the planets’ hidden regularities, i.e. ‘save’ the appearances. Plato’s pedagogy of three disciplines, mathematics, music and astronomy embodies the belief that mathematics is the way to the perception of the Good, the highest order of timeless form embodying precision, functional coherence and universality (Timaeus, Republic).

Paradigms contain, or exemplify for research programs) these components:

A world view or ontology: The two-sphere universe defines a ‘space’ within which celestial motions occur, bounded by the celestial sphere and the spherical and concentric earth. Celestial spheres undergo timeless uniform rotation from the moon’s orbit beyond. According to Aristotle, the four Empedoclean terrestrial ‘elements’ have distinctive natural motions of gravity and levity in radial earth-centered directions only. They are thus substantively distinct from a fifth element composing celestial objects, such as the moon and the sphere carrying it. The lunar dichotomy distinguishes two domains of motion and substance: (i) The celestial contains uniformly rotating geocentric spheres and is timeless (eternal in motion and substance). (ii) The terrestrial, which is subject to a multiplicity of episodes of generation and corruption, forced as well as natural motions, tripartite ‘souls’ (activities: vegetative, animative and cognitive), substantial transmutation and chance encounters.

Geometrical optics holds in both celestial domains: Rectilinear rays, perspective theory, image and shadow projection, is central to the empirical arguments for the two-sphere universe as they appear from Aristotle (his theory of the rainbow in De Caelo) through Ptolemy and beyond. (M.A. Smith, 2014)

Overall research objectives exemplify characteristic epistemic values natural and forced motions, final, material and efficient causes added to Plato’s geometrical and numerical ideals. They are codified in problems and expressed in questions addressed to the community. Observational ‘appearances’ should be ‘saved’ with geometrical constructions using homocentric spheres with axes adjusted post hoc at various angles and at various rotational speeds. These objectives are in accord with Plato’s program of reducing celestial wanderings to kinematic (geometry of motion) regularity.

In Aristotle’s cosmology terrestrial motions are to be explained by natural life cycles of kinds (animals and plants) and radial natural locomotion for the four Empedoclean elements. Horizontal trajectories are ‘forced’, caused and sustained, by external applied forces. Water and Earth can be forced upward against natural gravity, as Fire and Air can be constrained downward against their natural levity. The terrestrial objects we encounter are mixtures of various proportions of these elements, and their transmutations explain various geological and meteorologyical phenomena, such as volcanism, rain, springs, etc.

Preferred research problems include differences between theoretical expectations and observed planetary orbits (empirical anomalies). Plato’s motion of the ‘same’ (diurnal rotation) versus various motions of the ‘other’ (eastward motions unique to each planet) are an initially formulated constraint on solutions to these problems (Republic). Kuhn calls these puzzles, and are problems, whose possible solutions are specified by the paradigmatic ontology and research objectives. Puzzle solutions are constrained by a negative heuristic, which protects core beliefs, and can be prioritized by positive heuristics that guide further inquiry in the paradigm (Lakatos, 1970, Wimsatt, 1980). The formulation and pursuit of solutions to well defined puzzles are what Kuhn calls normal science.

Preferred empirical procedures: Empirical rules and heuristics, instruments, reliable informational processes are drawn from geometrical optics and perspectival construction, and from Aristotelian mechanics. In the Structure Kuhn embraces Gestalt perception, a holistic but ambiguous cognitive response to sensory inputs. Gestalt perceptions are legitimately employed for identifying and reidentifying and naming stars and galaxies, as the constellation Ursa Major, has always been used for identifying and re-identifying Polaris. Such methods remain embedded in the names we give to celestial objects, e.g. Alpha Centaurus.

Theoretical problem-solving protocols (Cf. Lakatos’ heuristics, 1970): Resolve an anomaly by adding a concentric sphere or post hoc adjustment of inclination and rotation for a match with quantitative and qualitative features of observed planetary ‘wanderings’. The imperative to conserve embedded uniformly rotating spheres concentric with the earth, is a negative heuristic prioritizing the retention of core cosmological assumptions.

Comment: Heuristics are guides or strategies that facilitate but do not guarantee the achievement of a desired goal. Possible paths to a goal, the location of a desired object, can easily exceed limitations of human activity, so we use selective constraints or biases to narrow these possibilities to some that we, with our current powers, can implement. A bias can contain information as where the object can be found or how it might appear in various circumstances. Biases should be useful in placing the goal within our powers of search, but they can also misdirect us. The object can be mistakenly conceived or nowhere near where we think it is. Certain questions contain such biases, those that...