replacement of the three vehicles with the one vehicle [開三顕一] ( kaisan-ken’ichi): Also, “opening the three vehicles and revealing the one vehicle.” A reference to Shakyamuni’s statement in the Lotus Sutra that the three vehicles are not ends in themselves—though other, provisional, sutras teach that they are—but expedient means by which he leads people to the one vehicle of Buddhahood. The three vehicles are the teachings expounded for voice-hearers, cause-awakened ones, and bodhisattvas, respectively. The one vehicle of Buddhahood means the teaching that enables all people to attain Buddhahood and corresponds to the Lotus Sutra. Shakyamuni Buddha first preached the various provisional teachings, or the three vehicle teachings, as an expedient means to help people develop the capacity to understand and receive the one vehicle teaching. In the Lotus Sutra, he declares that the earlier teachings have been set forth as expedient means to prepare people for the teaching of the sutra, which is the supreme vehicle of Buddhahood, the goal of the Buddhist practice. This concept is expressed as the replacement of the three vehicles with the one vehicle. T’ien-t’ai (538–597) explains the meaning of replacing the three vehicles with the one vehicle in The Profound Meaning of the Lotus Sutra, where he defines it as the principal doctrine of the theoretical teaching (first half) of the Lotus Sutra. T’ien-t’ai further divided the principle into two—the concise replacement of the three vehicles with the one vehicle and the expanded replacement of the three vehicles with the one vehicle. The concise replacement refers to the first part of the “Expedient Means” (second) chapter (through the end of the fifth verse section of that chapter, which concludes with Shāriputra’s words, “When we hear this Law / we will be filled with great joy”). This part centers on “the true aspect of all phenomena,” that is, the ten factors of life. The expanded replacement refers to Shakyamuni’s further elaboration on his meaning from a variety of angles, using parables and other means of explanation. This elaboration lasts from the latter half of the “Expedient Means” chapter, which begins with Shakyamuni’s words to Shāriputra, “Three times you have stated your earnest request,” through the end of the “Prophecies” (ninth) chapter.