At the time that the great Central Asian translator, Kumārajīva (334–413), was working with a multi-ethnic translation team in the Chinese capital of Chang’an (a city of between 300,000 and 500,000 people at the time), Buddhism had undergone nearly a thousand years of adaptive evolution and several hundred texts were catalogued as part of the Buddhist canon. By the seventh century, that number had grown to over a thousand. These texts all purported to be authentic renderings of Buddhist teaching. But in actuality they often had quite disparate historical and cultural origins, and this presented Chinese Buddhist scholars with immense hermeneutical challenges. Drawing on evidence internal to key Buddhist scriptures, different systems were devised for classifying and ranking Buddhist teachings and texts, and these became the basis of competing, textually-defined schools of Buddhism, the foremost being the Consciousness-Only (Weishizong, 唯識宗), Heavenly Terrace (Tiantai zong, 天台宗 ), Pure Land (Jingtu zong, 淨土宗) and Flower Ornament (Huayan zong, 華嚴宗) schools.