Part one: Introducing theology. 1. The habit of theology -- 2. The task of theology -- Part two: the role of philosophy in theology. 3. General principles -- 4. The existence and concept of God -- 5. Theodicy and the idea of salvation -- 6. The possibility and historicity of revelation -- 7. The philosophical principle of order in theology -- Part three: Scripture as a source in theology. 8. The authority of Scripture: canonicity -- 9. The authority of Scripture: inspiration -- 10. The authority of Scripture: inerrancy -- 11. The interpretation of Scripture: the letter -- 12. The interpretation of Scripture: the spirit -- Part four: tradition as a source in theology. 13. The nature of tradition -- 14. The liturgy and Christian art -- 15. Fathers, councils, and creeds -- 16. The sense of the faithful -- Part five: aids to discernment in theology -- 17. Experience -- 18. The Magisterium -- Part six: plurality and unity in Catholic theology. 19. Soundings in theological history -- 20. The theological principle of order.