Towards the Modern Theory of Motion. Oxford Calculators and the new interpretation of Aristotle - ebook

The problem of the continuity of science from the medieval to the modern times of the 17^th century, when Galileo and Newton developed the correct theory of mechanics, occupied historians of science from the beginning of the 20^th century. Some believe that the fourteenth-century English scholars who created the School of Oxford Calculators and their French and Italian followers. with their solutions, laid the foundations for the development of modern physics. Others believe that medieval natural philosophy made no contribution to the development of modern science. The presented book is a voice in this discussion and an attempt to answer the question about the continuity of science. Considering how much has been discovered, edited and written about the Oxford Calculators, the book reviews and compares the results of our research with works of the other historians’ research into the intellectual heritage of these 14^th century English thinkers in order to enrich and update the views on the Oxford Calculators’ natural philosophy in perhaps its most fundamental aspect – at least from the point of view of Aristotle’s philosophy – namely the subject of “science of local motion.”

The discussion are mostly focused on topics that were important to medieval thinkers and not those that could be most interesting from the modern point of view, and the research are directed on the Oxford Calculators’ tradition in science toward a prospecting of the innovative character of their teaching, and here first of all against the background of Aristotelian theories, and then the subsequent search for possible innovations which could have inspired early modern scientists.

As the conclusions of the research on the theories of Oxford calculators are still formulated mainly on the basis of analyzes of incomplete printed texts, the critical editions of Latin texts are offered. These are not only the most famous Calculators’ works, such as William Heytesbury’s De tribus praedicamentis: de motu locali or John Dumbleton’s Part III of the Summa logicae et philosophiae naturalis, but also of a hither to unknown work by Richard Kilvington, i.e., his question on local motion and the question on local motion written by the anonymous author of the treatise De sex inconvenientibus.

Preface 7

Chapter I: Lives and Works of Oxford Calculators (Elżbieta Jung) 11

1. Richard Kilvington 13

2. Thomas Bradwardine 18

3. William Heytesbury 20

4. The Anonymous Author of the De sex inconvenientibus 22

5. John Dumbleton 29

6. Richard Swineshead 31

Chapter II: Theories of Local Motion before the Oxford Calculators (Elżbieta Jung) 37

1. Aristotle’s “Mathematical Physics” 37

2. Theories of Motion in Arabic Medieval Philosophy 43

3. The English Tradition in Mathematical Natural Science 50

Chapter III: Oxford Calculators on Local Motion (Elżbieta Jung, Robert Podkoński) 57

1. Richard Kilvington’s Theory of Local Motion 57

1.1. Motion with respect to its Causes 58

1.1.1. An Excess of Acting Power over Resistance – the Condition Necessary for Motion 59

1.1.2. Inalienable Conditions of Motion 61

1.1.2a. How to “Measure” an Active Power? 63

1.1.2b. How to “Measure” a Passive Power? 65

1.1.3. The Result of Action of Powers – Speed of Motion 67

1.2. Motion with respect to its Effect – the Distances Traversed and Time 79

2. Thomas Bradwardine’s Treatise on Local Motion 82

3. William Heytesbury’s Contribution to the Oxford Calculators’ Science of Local Motion 87

4. The Theory of Motion in the Anonymous Treatise: De sex inconvenientibus 93

4.1. The Causes of Accelerated Motion 99

4.2. The Motion of a Sphere 101

4.3. The Mean Speed Theorem 104

5. John Dumbleton on Local Motion 112

5.1. The Mean Speed Theorem 124

6. Richard Swineshead’s Speculative Science of Local Motion 125

Chapter IV: Towards Modern Mechanics? (Elżbieta Jung, Robert Podkoński) 159

The Novelty of Medieval Mechanics vis-à-vis Aristotelian and Galileian Theories… 184

Editions 189

Introduction (Elżbieta Jung, Joanna Papiernik, Robert Podkoński) 191

1. Richard Kilvington’s Question Utrum potentia motoris excedit potentiam rei motae from His Quaestiones super libros Physicorum 192

2. The Section De motu locali of William Heytesbury’s Regulae solvendi sphismata 193

3. The Question Utrum in motu locali sit in certa servanda velocitas from the Anonymous Treatise de sex inconvenientibus 201

4. Selected Fragments of Part III: De motu locali of John Dumbleton’s Summa logicae et philosophiae naturalis 204

5. Presentation of the Texts – Editorial Rules, the Contents of apparati critici, and Abbreviations Used 207

5.1. Richard Kilvington, Utrum in omni motu potentia motoris excedit potentiam rei motae 208

5.2. William Heytesbury, De motu locali 209

5.3. Anonymous, Utrum in motu locali sit certa servanda velocitas 210

5.4. John Dumbleton, De motu locali 210

Ricardus Kilvington, Utrum in omni motu potentia motoris excedit potentiam rei motae, Elżbieta Jung (ed.) 213

Guilelmus Heytesbury, De motu locali, Elżbieta Jung, Robert Podkoński (eds) 267

Anonimus, Utrum in motu locali sit certa servanda velocitas, Joanna Papiernik (ed.) 297

Johannes Dumbleton, De motu locali, Elżbieta Jung, Robert Podkoński (eds) 391

Bibliography 427

Index of Names 447

Summary 451