WHEN THE BUDDHA TAUGHT HIS DOCTRINES AND ORGANIZED MONASTIC orders (sanghas) during the sixth and fifth centuries B.C.E., northern India was experiencing a second period of urbanization. Its first period of urbanization had taken place along the Indus River, where the cities of the Harappan civilization (named after one of its major urban sites) flourished during the third and second millennia B.C.E. Most of the cities during the second period of urbanization were located around the mid¬dle or lower Ganges plain. Buddha, the muni or sage of the Shakya Republic, often traveled to and gave his sermons in cities such as Rajagriha, Sravasti, and Vaisali. Except for metropolitan Taxila, the northwestern region was quite rustic in comparison with the Ganges plain, and the Buddha himself never set foot in the northwestern area. By the time the Kushans ruled northern India, however, the northwest had become the political and economic core of South Asia. Buddhist institutions flourished in the northwest, Kushan kings patronized Buddhism, and as a result many legends about and relics of the Buddha in this area appeared there. During the early centuries of the common era, Buddhist monasteries developed into institutions far larger, more affluent, and much more complex than the earlier sanghas. Buddhist theology also became far more complicated than the pristine teachings of the Buddha had been. Among the many Buddhist schools of that time, Mahayana Buddhism became the most prevalent. Two mutually dependent features that dis¬tinguished it from earlier Buddhism should be mentioned. First, nihilism, the concept of "emptiness" (that is, the objects people see or feel do not exist, rather, they are only illusions of the subject), was embodied in ear¬lier forms of Buddhism. The Mahayana school of thought pushed this concept even further. Mahayana texts tended to treat everything as meaningless or nonexisting. Not only did the objects of observation not exist, but the observers themselves did not exist either. Second, ironically, this philosophy that absolutely denied the material world emerged at a time when Buddhist institutions were unprecedentedly wealthy, just like the surrounding society. So far there have been only a few pieces of evi¬dence suggesting that Buddhist monasteries actively participated in trade, but abundant evidence shows that they did receive large amounts of material patronage from traders, artisans, and other urban dwellers. The numerous votive inscriptions dated to the Kushan period attest to the material patronage to Buddhist monasteries.1 In the time of the Buddha, monks had to beg for food on a daily basis, but during the Kushan period most monasteries set out a large symbolic begging bowl to receive donations in the form of coins and precious items. The wealth that flowed into the monasteries not only produced mar¬velous art works in and on cave temples, on monumental stupas (giant mounts containing relics of the Buddha) and their surrounding railings, and on monastic walls and buildings, but this wealth also changed monas-teries into economic entities. Monasteries had to trade the donated valu¬ables for provisions in order to maintain the monks. Monastic establishments also took the lead in large construction projects, including monasteries and stupas. They had to coordinate the individual donations of single pieces of art into a much larger design. Buddhist sculptures were often the donations of individuals, as shown by inscriptions revealing the names and titles of the donors and indicating what blessings they hoped to receive in return. Nevertheless, the sculptures became inseparable con¬stituent parts of a much larger complex of monumental structures.

BUDDHISM AND MATERIAL CULTURE

In contrast to the asceticism that Buddhist monks were supposed to observe, Buddhist art at this time depicted lively urban life. From Central Asia to northern India, sculptures and murals in monastic settings depicted