Fritz Allhoff is Assistant Professor of Philosophy at Western Michigan University. He has published work in journals including American Journal of Bioethics, History and Philosophy of the Life Sciences, International Journal of Applied Philosophy, and Kennedy Institute of Ethics Journal.

Anand Jayprakash Vaidya is Assistant Professor of Philosophy at San José State University. His research is in Metaphysics & Epistemology, and Philosophy of Mind.

Contents

Text Sources and Credits viii

Acknowledgments xiii

General Introduction 1

Part I Logic and Epistemology 27

Introduction 27

Philosophy, Theology, Logic, and the Sciences 31

1 Augustine on Ancient Philosophy 31

2 Dialectica Monacensis (anonymous, twelfth century) on the Division of Science 43

3 Thomas Aquinas on the Nature and Scope of Sacred Doctrine 45

The Problem of Universals 59

4 Boethius Against Real Universals 59

5 John of Salisbury on the Controversy over Universals 63

6 The Summa Lamberti on the Properties of Terms 66

7 William Ockham on Universals 71

8 John Buridan on the Predicables 79

Illumination vs. Abstraction, and Scientific Knowledge 83

9 Augustine on Divine Ideas and Illumination 83

10 Thomas Aquinas on Illumination vs. Abstraction 87

11 Thomas Aquinas on our Knowledge of the First Principles of Demonstration 98

12 Henry of Ghent on Divine Illumination 103

13 Duns Scotus on Divine Illumination 110

Knowledge and Skepticism 117

14 Augustine on the Certainty of Self-Knowledge 117

15 Thomas Aquinas on whether the Intellect Can Be False 120

16 Henry of Ghent on whether a Human Being Can Know Anything 123

17 Nicholas of Autrecourt on Skepticism about Substance and Causality 134

18 John Buridan on Scientific Knowledge 143

Part II Philosophy Of Nature, Philosophy of The Soul, Metaphysics 151

Introduction 151

Hylomorphism, Causality, Natural Philosophy 157

19 Thomas Aquinas on the Principles of Nature 157

20 Thomas Aquinas on the Mixture of Elements 168

21 Giles of Rome on the Errors of the Philosophers 171

22 Selections from the Condemnation of 1277 180

23 John Buridan and the Impetus Theory of Projectile Motion 190

Human Nature and the Philosophy of the Soul 195

24 Augustine on the Soul 195

25 Averroës on the Immateriality of the Intellect 198

26 Siger of Brabant on the Intellective Soul 203

27 Thomas Aquinas on the Nature and Powers of the Human Soul 207

28 John Buridan on the Immateriality of the Soul 219

Metaphysics, Existence, and Essence 225

29 Avicenna on Common Nature 225

30 Thomas Aquinas on Being and Essence 227

31 John Buridan on Essence and Existence 250

God's Existence and Essence 255

32 Augustine on Divine Immutability 255

33 Anselm of Canterbury on God's Existence 259

34 Thomas Aquinas on God's Existence and Simplicity 266

Part III Practical Philosophy 303

Introduction 303

Goodness and Being 309

35 Augustine on Evil as the Privation of Goodness 309

36 Augustine on the Origin of Moral Evil 311

37 Boethius on Being and Goodness 318

38 Thomas Aquinas on the Convertibility of Being and Goodness 322

Freedom of the Will 325

39 Augustine on the "Divided Will" 325

40 Boethius on Divine Providence and the Freedom of the Will 331

41 Anselm of Canterbury on Free Will 337

42 Henry of Ghent on the Primacy of the Will 349

Virtues and Happiness 353

43 Boethius of Dacia on the Supreme Good 353

44 Thomas Aquinas on Happiness 358

Divine Law, Natural Law, Positive Law 361

45 Thomas Aquinas on Natural Law and Positive Law 361

46 John Duns Scotus on Natural Law and Divine Law 375

Suggestions for Further Reading 382

Index 388