Full context:   According to Anderson, "the four truths are recognized as perhaps the most important teaching of the Buddha." Yet, as early as 1935 Caroline Rhys Davids wrote that for a teaching so central to Theravada Buddhism, it was missing from critical passages in the Pali canon. According to Gethin, the four truths and the eightfold path are only two lists of "literally hundreds of similar lists covering the whole range of the theory and practice of ancient Buddhism." The position of the four truths within the canon raises questions, and has been investigated throughout the 19th and 20th centuries.