Primary sources for the philosophical foundations

The source map privileges the existing Katholon readers. Philosophical texts establish arguments and terminology; councils and papal documents identify Catholic doctrine and its authority; Scripture belongs to the revealed stage; historical sources establish what persons and communities actually said and did.

A citation is not decorative. The reader should be able to open the work, locate the question or passage, compare context and distinguish a text’s authority from the truth of an argument offered within it.

1. Vatican I · Dei Filius

   Used in Why first philosophy precedes apologetics. Open the complete reader context rather than relying on an isolated quotation.

2. Leo XIII · Aeterni Patris

   Used in Why first philosophy precedes apologetics. Open the complete reader context rather than relying on an isolated quotation.

3. Thomas Aquinas · Summa Theologiae I q.1–2

   Used in Why first philosophy precedes apologetics. Open the complete reader context rather than relying on an isolated quotation.

4. Aristotle · De anima

   Used in Realism and the external world. Open the complete reader context rather than relying on an isolated quotation.

5. Thomas Aquinas · De veritate

   Used in Realism and the external world. Open the complete reader context rather than relying on an isolated quotation.

6. Summa Theologiae I q.84–85

   Used in Realism and the external world. Open the complete reader context rather than relying on an isolated quotation.

7. Aristotle · De anima III

   Used in Sensation, abstraction and universal knowledge. Open the complete reader context rather than relying on an isolated quotation.

8. Thomas Aquinas · De anima

   Used in Sensation, abstraction and universal knowledge. Open the complete reader context rather than relying on an isolated quotation.

9. Summa Theologiae I q.79, 84–89

   Used in Sensation, abstraction and universal knowledge. Open the complete reader context rather than relying on an isolated quotation.

10. Thomas Aquinas · De veritate q.1

    Used in Truth, judgment, certainty and error. Open the complete reader context rather than relying on an isolated quotation.

11. Summa Theologiae I q.16–17

    Used in Truth, judgment, certainty and error. Open the complete reader context rather than relying on an isolated quotation.

12. Vatican I · faith and reason

    Used in Truth, judgment, certainty and error. Open the complete reader context rather than relying on an isolated quotation.

13. Aristotle · Metaphysics IV

    Used in Being and the first principles of thought. Open the complete reader context rather than relying on an isolated quotation.

14. Thomas Aquinas · De ente et essentia

    Used in Being and the first principles of thought. Open the complete reader context rather than relying on an isolated quotation.

15. Summa Theologiae I q.3–4

    Used in Being and the first principles of thought. Open the complete reader context rather than relying on an isolated quotation.

16. Aristotle · Physics II

    Used in The causal principle and real powers. Open the complete reader context rather than relying on an isolated quotation.

17. Thomas Aquinas · Summa Contra Gentiles I.13

    Used in The causal principle and real powers. Open the complete reader context rather than relying on an isolated quotation.

18. Summa Theologiae I q.2 a.3

    Used in The causal principle and real powers. Open the complete reader context rather than relying on an isolated quotation.

19. Aristotle · Physics III

    Used in Act, potency and the possibility of change. Open the complete reader context rather than relying on an isolated quotation.

20. Thomas Aquinas · Commentary on Physics

    Used in Act, potency and the possibility of change. Open the complete reader context rather than relying on an isolated quotation.

21. Summa Theologiae I q.9

    Used in Act, potency and the possibility of change. Open the complete reader context rather than relying on an isolated quotation.

22. Aristotle · De anima II

    Used in Hylomorphism: matter, form and the unity of bodies. Open the complete reader context rather than relying on an isolated quotation.

23. Thomas Aquinas · De principiis naturae

    Used in Hylomorphism: matter, form and the unity of bodies. Open the complete reader context rather than relying on an isolated quotation.

24. Summa Theologiae I q.75–76

    Used in Hylomorphism: matter, form and the unity of bodies. Open the complete reader context rather than relying on an isolated quotation.

25. Aristotle · Categories

    Used in Substance, accident and enduring identity. Open the complete reader context rather than relying on an isolated quotation.

26. Council of Trent · Eucharist

    Used in Substance, accident and enduring identity. Open the complete reader context rather than relying on an isolated quotation.

27. Summa Theologiae III q.75–77

    Used in Substance, accident and enduring identity. Open the complete reader context rather than relying on an isolated quotation.

28. Thomas Aquinas · De ente et essentia

    Used in Essence and existence in created beings. Open the complete reader context rather than relying on an isolated quotation.

29. Summa Theologiae I q.3 a.4

    Used in Essence and existence in created beings. Open the complete reader context rather than relying on an isolated quotation.

30. Summa Contra Gentiles II

    Used in Essence and existence in created beings. Open the complete reader context rather than relying on an isolated quotation.

31. Aristotle · Physics II

    Used in The four causes and complete explanation. Open the complete reader context rather than relying on an isolated quotation.

32. Thomas Aquinas · De principiis naturae

    Used in The four causes and complete explanation. Open the complete reader context rather than relying on an isolated quotation.

33. Summa Theologiae I q.44

    Used in The four causes and complete explanation. Open the complete reader context rather than relying on an isolated quotation.

34. Thomas Aquinas · First and Second Ways

    Used in Essential and accidental causal series. Open the complete reader context rather than relying on an isolated quotation.

35. Summa Contra Gentiles I.13

    Used in Essential and accidental causal series. Open the complete reader context rather than relying on an isolated quotation.

36. Aristotle · Metaphysics XII

    Used in Essential and accidental causal series. Open the complete reader context rather than relying on an isolated quotation.

37. Thomas Aquinas · Third Way

    Used in Contingency, necessity and dependent existence. Open the complete reader context rather than relying on an isolated quotation.

38. De ente et essentia

    Used in Contingency, necessity and dependent existence. Open the complete reader context rather than relying on an isolated quotation.

39. Vatican I · Creator

    Used in Contingency, necessity and dependent existence. Open the complete reader context rather than relying on an isolated quotation.

40. Thomas Aquinas · Fourth Way

    Used in Participation and received perfection. Open the complete reader context rather than relying on an isolated quotation.

41. De potentia q.3

    Used in Participation and received perfection. Open the complete reader context rather than relying on an isolated quotation.

42. Pseudo-Dionysius · Divine Names

    Used in Participation and received perfection. Open the complete reader context rather than relying on an isolated quotation.

43. Aristotle · Physics II

    Used in Finality, teleology and natural order. Open the complete reader context rather than relying on an isolated quotation.

44. Thomas Aquinas · Fifth Way

    Used in Finality, teleology and natural order. Open the complete reader context rather than relying on an isolated quotation.

45. Summa Contra Gentiles III

    Used in Finality, teleology and natural order. Open the complete reader context rather than relying on an isolated quotation.

46. Thomas Aquinas · De veritate q.1 and q.21

    Used in The transcendentals: unity, truth, goodness and beauty. Open the complete reader context rather than relying on an isolated quotation.

47. Summa Theologiae I q.5–6, 11, 16

    Used in The transcendentals: unity, truth, goodness and beauty. Open the complete reader context rather than relying on an isolated quotation.

48. Pseudo-Dionysius · Divine Names

    Used in The transcendentals: unity, truth, goodness and beauty. Open the complete reader context rather than relying on an isolated quotation.

49. Thomas Aquinas · Summa Theologiae I q.13

    Used in Analogy of being and language about God. Open the complete reader context rather than relying on an isolated quotation.

50. Summa Contra Gentiles I.30–34

    Used in Analogy of being and language about God. Open the complete reader context rather than relying on an isolated quotation.

51. Fourth Lateran Council · analogy

    Used in Analogy of being and language about God. Open the complete reader context rather than relying on an isolated quotation.

52. Aristotle · De anima

    Used in The human person: body and rational soul. Open the complete reader context rather than relying on an isolated quotation.

53. Council of Vienne · soul as form

    Used in The human person: body and rational soul. Open the complete reader context rather than relying on an isolated quotation.

54. Summa Theologiae I q.75–76

    Used in The human person: body and rational soul. Open the complete reader context rather than relying on an isolated quotation.

55. Aristotle · De anima III

    Used in Intellect, immateriality and universal knowledge. Open the complete reader context rather than relying on an isolated quotation.

56. Thomas Aquinas · Summa Contra Gentiles II.49–55

    Used in Intellect, immateriality and universal knowledge. Open the complete reader context rather than relying on an isolated quotation.

57. Summa Theologiae I q.79, 84–89

    Used in Intellect, immateriality and universal knowledge. Open the complete reader context rather than relying on an isolated quotation.

58. Aristotle · Nicomachean Ethics III

    Used in Will, freedom and rational appetite. Open the complete reader context rather than relying on an isolated quotation.

59. Thomas Aquinas · De malo q.6

    Used in Will, freedom and rational appetite. Open the complete reader context rather than relying on an isolated quotation.

60. Summa Theologiae I-II q.6–17

    Used in Will, freedom and rational appetite. Open the complete reader context rather than relying on an isolated quotation.

61. Thomas Aquinas · Summa Theologiae I-II q.90–97

    Used in Natural law and objective moral order. Open the complete reader context rather than relying on an isolated quotation.

62. Romans 2:14–16

    Used in Natural law and objective moral order. Open the complete reader context rather than relying on an isolated quotation.

63. Leo XIII · Libertas

    Used in Natural law and objective moral order. Open the complete reader context rather than relying on an isolated quotation.

64. Vatican I · faith and reason

    Used in Natural science and metaphysics. Open the complete reader context rather than relying on an isolated quotation.

65. Leo XIII · Providentissimus Deus

    Used in Natural science and metaphysics. Open the complete reader context rather than relying on an isolated quotation.

66. Thomas Aquinas · Commentary on Boethius De Trinitate

    Used in Natural science and metaphysics. Open the complete reader context rather than relying on an isolated quotation.

67. Thomas Aquinas · Summa Theologiae I q.2

    Used in Natural theology and the order of demonstration. Open the complete reader context rather than relying on an isolated quotation.

68. Vatican I · Dei Filius

    Used in Natural theology and the order of demonstration. Open the complete reader context rather than relying on an isolated quotation.

69. Romans 1:18–21

    Used in Natural theology and the order of demonstration. Open the complete reader context rather than relying on an isolated quotation.

70. Summa Theologiae I q.3–26

    Used in The divine attributes from the first cause. Open the complete reader context rather than relying on an isolated quotation.

71. Fourth Lateran Council

    Used in The divine attributes from the first cause. Open the complete reader context rather than relying on an isolated quotation.

72. Vatican I · Dei Filius ch.1

    Used in The divine attributes from the first cause. Open the complete reader context rather than relying on an isolated quotation.

73. Thomas Aquinas · Summa Theologiae

    Used in The scholastic question: objections, proof and replies. Open the complete reader context rather than relying on an isolated quotation.

74. Medieval disputation and scholasticism

    Used in The scholastic question: objections, proof and replies. Open the complete reader context rather than relying on an isolated quotation.

75. Vatican I · Dei Filius ch.2–3

    Used in From natural theology to the possibility of revelation. Open the complete reader context rather than relying on an isolated quotation.

76. Dei Verbum

    Used in From natural theology to the possibility of revelation. Open the complete reader context rather than relying on an isolated quotation.

77. Summa Theologiae II-II q.1–6

    Used in From natural theology to the possibility of revelation. Open the complete reader context rather than relying on an isolated quotation.

78. Aquinas · Five Ways

    Used in The five ways. Open the complete reader context rather than relying on an isolated quotation.

79. Aristotle · Metaphysics XII

    Used in First mover. Open the complete reader context rather than relying on an isolated quotation.