In their debate on whether or not the young should be allowed to study history, Degory Wheare and Gerhardus Vossius quote Bartholomäus Keckermann and state that he wants to exclude the young from studying history, Wheare arguing for Keckermann’s purported position, Vossius opposing it. Their disagreement is part of a larger controversy on the relevance of history for moral instruction in general, contemplating the question whether or not history is best understood as ‘philosophy teaching by example.’ But the interpretation of Keckermann’s position presupposed by both Wheare and Vossius is wrong. Keckermann’s Ramist predecessors argued against a central presupposition of Wheare’s views, i.e., the exclusion of the young from studying moral philosophy. Keckermann’s own position in this regard is not fully clear. But a closer analysis of his distinction between methods for writing and for reading history shows that Keckermann did want the young to study history. If Keckermann had believed that such exclusion were necessary, it could only have been related to reading historical texts, not to writing them: writing texts about historical figures or events does not require moral precepts, but only the application of certain logical tools. A view that implies that writing a historical text should be possible for students, whereas reading such a text would go beyond their capabilities, is absurd. Hence, we can assume that Keckermann expected the young to study both history and moral philosophy.

This essay explores Kant’s concept of absolute space in the Metaphysical Foundations from the perspective of the development of the relationist interpretation of bodily interactions in the center-of-mass reference frame, a strategy that Huygens had originally pioneered and which Mach also endorsed. In contrast to the interpretations of Kant that stress a non-relationist, Newton-inspired orientation in his critical period work, it will be argued that the content and function of Kant’s utilization of this reference frame strategy places him much closer to Huygens’ relationism than the absolute notions of space and motion favored by Newton and Euler.

Historia, as both a type of critical inquiry and a source of information about nature and the human world, is a key category in Spinoza’s Tractatus theologico-politicus (1670). In this work, the Latin word cannot be simply and invariably translated as “history,” not even if we add the proviso that its meaning wavers inevitably between “history” and “story,” for its semantic range is too broad and complex. At the two ends of the semantic spectrum we have the impartial report, on the one hand, and the creations of sheer fantasy (phantasmata and nugae), on the other. Historia may therefore denote the detached observation of nature and the philological analysis of a text, but it can also refer to the free exercise of the imagination in a variety of narrative contexts. While Spinoza denies that the inquiry resulting from historia and its products may have true cognitive value, he acknowledges that historia plays a fundamental role in society and politics. The reason is that historia and the imagination are bound up together by a special relationship. This is apparent at all levels of the historical engagement with reality (description, criticism and fiction), but is particularly true in the case of religion, moral norms and belief systems, for in this variegated domain the link between imagination and historia functions as the connective tissue that keeps societies united and functioning. This specific nexus of imagination and historia is Spinoza’s original contribution to the early modern notion of “moral certainty.” More importantly, it is only at this level that Spinoza grants a modicum of intelligibility (perceptibilitas) to the ‘historical’ productions of the imagination, be they signa, revelationes, or even nugae. The fact remains, though, that to a certain extent humans keep having a distorted grasp of reality, indeed hallucinate, even when their ‘historical’ accounts of reality are socially and politically productive. Here the key element is the notion of fictional continuity based on a socially constructed trust (fides historiarum) in narrative accounts of reality: the imagination turns reality into stories, but in so doing it keeps the otherwise constitutively hallucinatory nature of humans at bay and under control. Perceptibilitas, that is, the ability to provide acceptable cognitive solutions between intelligible knowledge and moral certainty, is ultimately what defines the contribution of the imagination to the human work of knowledge.

The 1648 exchange between Descartes and Arnauld focuses on several distinct but intertwined topics concerning Descartes’s philosophy of mind. Descartes’s acknowledgment of thinking as the essence of the mind implied a strong ‘actualist’ view of this essential activity. Arnauld’s objcetions reveal the problematic implications of this ontology of mind, from the role of memory and the temporal nature of our thought to the radical challenge of giving the status of an essence to such a temporal activity.

In The Sea–Mans Kalendar (1636 [1638?]), Henry Bond predicted that magnetic declination would be 0° in 1657, and would then increase westerly for (at least) 30 years. Based on these predictions, Bond went on to claim in The Longitude Found (1676) that, by using his model of magnetism, he can offer a technique for determining longitude. This paper offers an assessment of Bond’s method for longitude determination and critically evaluates Thomas Hobbes’s so–far neglected response to Bond’s proposal in Decameron physiologicum (1678), in which Hobbes complains about what he takes to be Bond’s implicit natural philosophy and about his use of spherical trigonometry.

The early history of thermometry is most commonly described as the result of a continuous development rather than the product of a single brilliant mind, and yet scholars have often credited the Italian physician Santorio Santori (1561–1636) with the invention of the first thermometers. The purpose of using such instruments within the traditional context of Galenic medicine, however, has not been investigated and scholars have consistently assumed that, being subject to the influence of atmospheric pressure and en­vironmental heat, Santorio’s instruments provided unreliable measurements. The discovery that, as early as 1612, Santorio describes all vacuum-related phenomena as effects of the atmospheric pressure of the air, provides ample room for reconsidering his role in the development of precision instruments and the early history of thermometry in particular. By drawing on a variety of written and visual sources, some unpublished, in the first part of this article I argue that Santorio’s appreciation of phenomena related to the weight of the air allowed him to construct the first thermometers working as sealed devices. Finally, in the second part, I consider Santorio’s use of the thermometer as related to the seventeenth-century medical practice and his way to measure the temperature as based on a wide sample of individuals.

Though he is known primarily for his mathematics, John Wallis (1616–1703) was also a prominent natural philosopher and experimentalist. Like many experimental philosophers, including his colleagues in the Royal So­ciety, Wallis sought to identify the mathematical laws that govern natural phenomena. However, I argue that Wallis’s particular understanding of the laws of nature was informed by his reading of a thirteenth–century optical treatise by Robert Grosseteste, De lineis, angulis et figuris, which expresses the principle that “Nature doth not work by Election.” Wallis’s use of this principle in his Discourse of Gravity and Gravitation (1675) helps to clarify his understanding of natural laws. According to Wallis, since nature cannot choose to act one way or another, natural phenomena are unfailingly regular, and it is this that allows them to be predicted, generalized, and described by mathematical rules. Furthermore, I argue that Wallis’s reading of Grosseteste reveals one way that medieval scholarship contributed to the “mathematization of nature” in the early modern period: historically–minded scholars like Wallis found insightful philosophical principles in medieval sources, and they transformed and redeployed these principles to suit the needs of early modern natural philosophy.

This paper deals with Descartes’s and Roberval’s attempts to devise and describe the center of agitation of a composite pendulum. This episode has received some attention in the recent literature. It is usually depicted as the first step in the development of a general procedure for establishing the center of oscillation of a pendulum. My aim is to explore the different physical concepts and assumptions which informed the two mathematical accounts of the composite pendulum. I will argue that force, agitation, heaviness, or resis­tance of air essentially meant different things for Descartes and Roberval. As a result, the physical phenomena covered by the two geometrical procedures were quite distinct, and both mathematicians envisaged different roles of these phenomena within their agenda of studying nature.

I analyze in this article the different ways in which Descartes uses abstraction in the Regulæ, discussing his project of a mathematical physics, the role of the imagination, and the status of numbers. I also try to show that the doctrine of simple natures cannot be well accommodated with the theory of abstraction developed in Rule 14, having instead a greater affinity with Descartes’ later theory of abstraction and exclusion (from the period after the Meditationes), in which imagination plays no role and everything happens at a strictly intellectual level. This interpretation is supported by the recent discovery of the Cambridge manuscript, which almost certainly records an early stage of composition and in which the doctrine of simple natures is absent, thus being very probably a later development.

When Descartes made his scientific work public, he ushered in a worldview based almost entirely on mechanical motion, which brought along a complete rejection of “occult” forces. Thus, the foundation of astrology was equally rejected by many prominent Cartesians. However, the popularity of Descartes’ system lead to its rapid adoption by many subjects, astrology included. Here, I will take a look at the curious case of Claude Gadroys, whose primary work, Discours sur les influences des astres (1671), defends a mechanical account of astrology that accords with Descartes’ principles. Gadroys’ Discours employs a sophisticated strategy to rehabilitate astrology of the 17th century against Pico della Mirandola, among other critics. Gadroys’ theory even incorporates Descartes’ discovery, contra the scholastics, that the sublunary and celestial spheres do not differ in kind. Surprisingly, Gadroys uses Descartes’ discovery to substantiate the stars influencing the Earth, whereas earlier astrologers required such a distinction. Gadroys’ adoption of Cartesian philosophy highlights two major theses. First, the advent of mechanical philosophy in no way necessitated the downfall of astrology; instead, it merely changed the direction of astrological explanation for those that followed current science. Second, it shows the selective nature of Cartesian explanation and hypotheses.

This essay explores the parallel development of fencing theory and philosophy in early modern Europe, and suggests that each field significantly influenced the other. Arguably, neither philosophy nor fencing would be the same today had the two not been engaged in this particular cultural symbiosis. An analysis is given of the philosophic content within several historical fencing treatises and of the position of fencing in seventeenth and eighteenth-century education and courtly life. Two case studies are then examined: the influence of the fencing master Charles Besnard on the intellectual development of Descartes, and the fencing master William Hope’s appropriation of the ideas of John Locke.

For Erasmus, the two fountains streaming milky juice—a new mother’s breasts—represent powerful symbols of love and authority. Erasmus describes the mother’s breasts as fountains oozing love to the sucking child. Elizabeth Clinton extends the image of Mother to represent God, reminding the nursing mother that when she looks on her sucking child, she should remember that she is God’s new born babe, sucking His instruction and His word, even as the babe sucks her breast. Dorothy Leigh extends the image of the nursing mother to an image of Christ himself. Mother’s love, especially a breast-feeding or “lying in” mother’s love, is one of the most authoritatively gendered representations of love. Issues of gender and authority converge often around the image of the breast-feeding mother. Drawing on the image of the nursing mother, Dorothy Leigh and other early modern writers actively engaged in the most contentious and public debates of their day, including the authority of men, preachers and kings.

This essay examines René Descartes’ Meditations on First Philosophy. It argues that the evil genius is the meditator who narrates Meditations and that Descartes’ goal in Meditation One is to transform his readers into evil geniuses. This account of the evil genius is significant because it explains why the evil genius must be finite and why it cannot call mathematics or logic into doubt. Further, it highlights the need to read the Meditations on two levels—one examining the meditator’s line of thinking on its own terms and the other exploring Descartes’ reasons for depicting the meditator’s progress in the way that he does.

The origins of demography as a scientific discipline are usually seen as intimately connected to the organisational and economic needs of the early modern state. This paper, by contrast, presents an early demographic enterprise that falls outside this framework. The calculations performed by the Italian Jesuit Giovanni Battista Riccioli in an appendix to his Geographia et hydrographia reformata (“Geography and hydrography brought up to date,” 1661) are the first systematic attempt presently known to arrive at an estimate of the entire world population. Yet they appear to have no political purpose and rather belong to a learned, bookish tradition of demographical thinking that may be termed “humanist”. The article starts from a summary of Riccioli’s life, of the book wherein his demographic exercise is contained and of this exercise itself. Thereafter, Riccioli’s motives, sources, methodology and results are discussed. By way of conclusion, some preliminary reflections on the place of Riccioli and the humanist tradition in the early modern history of demography as a whole are offered. Two appendices present a translation of the Coniectura and tabulate its literary sources in order to provide some possible starting points for a study of the aforementioned tradition.