This article examines the nineteenth-century debate about scientific method between John Stuart Mill and William Whewell. Contrary to standard interpretations (given, for example, by Achinstein, Buchdahl, Butts, and Laudan), I argue that their debate was not over whether to endorse an inductive methodology but rather over the nature of inductive reasoning in science and the types of conclusions yielded by it. Whewell endorses, while Mill rejects, a type of inductive reasoning in which inference is employed to find a property or (...) cause shared by the observed members of a class, which is generalized to all its members, including the unobserved ones. Because of this, Whewell’s inductivism, unlike Mill’s, is able to yield theoretical hypotheses referring to unob-servables such as molecules and light waves. This is contrary to the claims of some critics of inductivism who argue that inductivism is unable to yield such hypotheses. Moreover, I suggest that Whewell’s view of induction conforms more closely than Mill’s view to the practice of scientists such as Kepler, Newton, and Fresnel, who do attempt to discover laws involving unobservables. (shrink)

As the seventeenth century progressed, there was a growing realization among those who reflected on the kind of knowledge the new sciences could afford (among them Kepler, Bacon, Descartes, Boyle, Huygens) that hypothesis would have to be conceded a much more significant place in natural philosophy than the earlier ideal of demonstration allowed. Then came the mechanics of Newton's Principia, which seemed to manage quite well without appealing to hypothesis (though much would depend on how exactly terms like "force" and (...) "attraction" were construed). If the science of motion could dispense with causal hypothesis and the attendant uncertainty, why should this not serve as the goal of natural philosophy generally? The apparent absence of causal hypothesis from the highly successful new science of motion went far towards shaping, in different ways, the account of scientific knowledge given by many of the philosophers of the century following, notable among them Berkeley, Hume, Reid, and Kant. This "Newtonian" interlude in the history of the philosophy of science would today be accounted on the whole a byway. The Principia, despite its enormous achievement in shaping subsequent work in mechanics, was from the beginning too idiosyncratic from an epistemic standpoint to serve as model for the natural sciences generally. (shrink)

: This study of the concept of orbit is intended to throw light on the nature of revolutionary concepts in science. We observe that Kepler transformed theoretical astronomy that was understood in terms of orbs [Latin: orbes] (spherical shells to which the planets were attached) and models (called hypotheses at the time), by introducing a single term, orbit [Latin: orbita], that is, the path of a planet in space resulting from the action of physical causes expressed in laws of nature. (...) To demonstrate the claim that orbit is a revolutionary concept we pursue three lines of argument. First we trace the origin of the term; second, we document its development and specify the meaning of the novel term as it was introduced into astronomy by Kepler in his Astronomia nova (1609). Finally, in order to establish in what sense the concept is revolutionary, we pay attention to the enduring impact that the concept has had on the relevant sciences, in this case astronomy and indeed physics. We claim that orbit is an instance of a revolutionary concept whose provenance and use can provide the insights we are seeking. (shrink)

Some of Kepler's works seem very different in character. His youthful Mysterium cosmographicum (1596) argues for heliocentrism on the basis of metaphysical, astronomical, astrological, numerological and architectonic principles. By contrast, Astronomia nova (1609) is far more tightly argued on the basis of only a few dynamical principles. In the eyes of many, such a contrast embodies a transition from Renaissance to early modern science. I suggest that Karl Popper's fallibilist and piecemeal approach, and especially his theory of errors, might prove (...) extremely helpful in resolving such alleged tension. By abandoning the perspective of the inductivist philosophy of science, which is forced by its own standards to portray Kepler as a "sleepwalker", I focus on the method he followed: he never hesitated to discuss his own intellectual journey, offering a rational reconstruction of the series of false starts, blind alleys and failures he encountered. The critical dialogue he managed to establish in private correspondence with fellow astronomers he later transplanted into his printed works, whose structure closely resembles that of a dialogue, however implicit. (shrink)

This article deals with the methodological procedures employed by Johannes Kepler, particularly those used in the process of elaboration of the two first laws of planetary movements. Its aim is to show that the astronomical practice of Kepler is linked with the proposal of (physical and mathematical) hypothesis and with valuing precision in observational data, with the goal of obtaining, by means of rigorous procedures, the (mathematically expressed) regularities of planetary motions. It was only afterwards that Kepler looked for an (...) explanation of the regularities (laws) discovered, formulating the hypothesis of the magnetic action exerted by the Sun, which is located at the physical center of the system. In the new astronomy, he modifies the methodological status of astronomical hypotheses in the beginning of 17th century (present in Ptolemy, Copernicus and Brahe), promoting the passage from a mathematical descriptive astronomy to a physical-mathematical explicative astronomy. (shrink)

The paper, as a continuation of the paper Hanzel , provides a methodological generalization of Newton’s method of theory construction as applied in Book I and Book III of his Principia. It reconstructs also the method of measures applied in those books. Finally, it shows how the term “harmonic law” changes its meaning in the Principia.