Henri de Lubac's Aspects of Buddhism is an introduction that discusses the origins of Buddhism, the life of Siddhartha Gautama Buddha, and its key principles such as the Four Noble Truths and the concept of nirvana. It also outlines the differences between the two main schools of Buddhism, Hinayana and Mahayana, and the significance of the monastic community (Sangha) in the search for enlightenment. De Lubac outlines the core of Buddhist doctrine, including the Four Noble Truths, which explain suffering and the path to its end, and the concept of nirvana, the ultimate goal of spiritual attainment. It also covers the fundamental differences between the two main branches of Buddhism, known as Hinayana (or Theravada) and Mahayana, and their respective characteristics.