Making a history of the principle of inertia, as of any other principle or concept, is a complex but still possible operation. In this work it has been chosen to make a back story which seemed the most natural way for a reconstruction. On the way back, it has been decided to stop at the 6th century CE with the contribution of Ioannes Philoponus. The principle he stated, although very different from the modern one, is certainly associated with it. Going (...) back in time it is still possible and of course one could proceed to the origins of the homo sapiens who perhaps posed the problem of why a club thrown with his hand could go so far from him. But the similarities that one can find with the modern principle are very vague, too perhaps. Without going so far one could see an embryonic idea of the principle of inertia in the atomistic theory of Democritus in the 5th century BCE. The motion of atoms whirling with no apparent reason can suggest the idea that a body can also move with no reason. But the transition from the atom, a metaphysical being, to the body, an empirical being, is far from immediate. (shrink)

First recorded in the 14th century, the analogy of spit-roast meat argues that expecting the Sun to rotate around a strictly immobile Earth would be just as ludicrous as trying to move the fire around the roasting meat. On the contrary, it should be the Earth that spins upon itself in order to glean, from all possible angles, all the benefits of the Sun, just as it is the meat’s responsibility to turn on the spit before the motionless fire for (...) it to be perfectly cooked on all sides. Aimed at demonstrating, in geocentricism, the plausibility of the rotation of the Earth and, in heliocentrism, at supporting the physical reality of this terrestrial rotation, nowadays this analogy barely elicits more than an amused, or even condescending, smile. However, its continued long-term existence and its frequency of use — from the 14th to the 19th century, we found it mentioned by no less than 45 different authors — incited us to finally pay attention to it. We then noticed that beyond its explicitly cosmological scope, it raises, in its own way, the question of the purpose of the natural world: had the latter been conceived based upon humankind, then it is normal, despite what this analogy advocates, that the Sun is at the service of something more important than itself by rotating, to the profit of humankind, around the Earth; conversely, since such an infringement of the rule of common sense, as illustrated by this analogy, can neither be justified nor tolerated, it is up to the Earth to move around the Sun. Tracing the vicissitudes of this analogy, over 6 centuries, is thus not only about reconstructing the largely forgotten history of a presently obsolete analogy, but also about discovering the deeper meaning, henceforth incomprehensible, behind it. In describing how this meaning became progressively lost, one can finally pro­vide an understanding of why, in the present day, we are no longer capable of more than an amused smile when happening upon it! (shrink)

In what is quite possibly the most famous passage of the De revolutionibus, Copernicus implies that nobody could ever place this supreme flaming torch that is the Sun in another or better place than that from which it can illuminate everything simultaneously, namely the centre of this extremely beautiful temple that is our world. Considering the fact that he leaves an interrogatory twist to this argument of convenience, and since he makes this statement without any justification as it seems entirely (...) evident to him, certain Copernicans choose to illustrate this by means of an analogy: if indeed the Sun must be positioned thus, it is because the most appropriate place for the torch intended to illuminate the room is at its centre, and not in one of its corners. Despite the heliosophy of the Renaissance having been shared by both geocentrists and Copernicans alike, this "torch" argument does not appear to have achieved much success: rarely adopted by the Copernican camp, it was even contested by some of them; as for the geocentrists, it held no appeal for them whatsoever. Did this argument of convenience therefore not benefit from the self-evidence attributed to it by Copernicus, and from, in his wake, it's continued support by a good many commentators? As is often the case when it comes to the history of thought, the pseudo-obviousness of this argument is merely the fruit of a blatant anachronism: presenting heliocentrism as the cosmological system that finally grants the Sun its worthy centrality by placing it in the centre of the room and not in a corner, is to ignore the fact that this star of the day already enjoyed, in geocentrism, a centrality esteemed to be perfectly in keeping with both its dignity and its inherent illuminative function. Having lost their grasp on this worldview that no longer belonged to them, the Copernicans thus put forward an argument which, for the geocentrists, is worthless. Yet they could have argued the objective superiority of their centrality over that accorded to the Sun by geocentrism: while the latter is only numerical, on a purely planetary scale, and frankly fictitious, the former is thoroughly spatial, of cosmic proportions and, at least on first approximation, very real. In order to produce arguments of convenience that could carry their own weight, the protagonists of the new cosmology would have benefited from getting to know the world vision of their adversaries a little better instead of addressing them from their own point of view; similarly, instead of treating as an obvious fact that which is only evident to one of the two parties present, historians of scientific thought would also be well advised to have a better understanding of the world vision of those who history now considers as the losers! (shrink)

This is about the tension between Epicurean and Galilean accounts of motion in Gassendi. For my more recent thoughts on this, see http://philpapers.org/rec/LOLCEG.

In this article I will explore the relationship between man and animal as presented by Ovid in some of his rape stories narrated in the Metamorphoses. The stories I will discuss are those of Actaeon and Callisto, the rape of Europa and the rape of Proserpina. Against Ovid’s background, I will examine Rembrandt’s version of these stories. In other words, I will investigate how Ovid’s textual construction of animals vs. humans relates to Rembrandt’s painterly construction of them. Accordingly, I will (...) explore how Rembrandt’s presentation of animals in his mythical images may reflect some of the prevalent attitudes of the period towards animals. My final goal is to address the question of the sublime in Rembrandt’s myths of human-animal transformation. Specifically, I will try to show that in his work the animals become agents of the sublime on a par with humans and gods. I will argue that similarly to Ovid’s reader, Rembrandt’s viewer experienced awe, amazement, even terror in front of his depictions of sublime passions, impossible disguises and transformations, his stories of violence, enacted collaboratively between man and animal. (shrink)

I argue that Descartes and the Cartesians are likely in agreement that logic is an ars cogitandi whose aim is to perfect the ingenium by the exercise of its operations: ideating, judging, discoursing, and ordering. We can see that these elements are the underpinning of both the Regulae and the Discourse on Method, and thus, like Adrien Baillet and others in the seventeenth century, we can understand these two works as embodying Descartes’ “logic,” despite Descartes’ notorious anti-logic Renaissance rhetoric in (...) both writings. (shrink)

I consider two events in late seventeenth-century philosophy: the condemnation of Cartesianism by the church, the throne, and the university and the noncondemnation of Gassendism by the same powers. What is striking about the two events is that both Cartesians and Gassendists accepted the same proposition deemed heretical. Thus, what was sufficient to condemn Cartesianism was not sufficient to condemn Gassendism. As a result, I suggest that to understand what is involved in condemnation one has to pay close attention to (...) the intellectual and/or social context and to rhetorical strategy, not just to the propositions condemned. In this case, what is at stake are some of the central propositions of corpuscularianism and the mechanical philosophy. (shrink)