Since the beginning of the serious study of the history of Buddhist art in the 1890s, the earliest phase, lasting until the 1st century CE, has been described as aniconic; the Buddha was only represented through symbols such as an empty throne, Bodhi tree, a riderless horse with a parasol floating above an empty space (at Sanchi), Buddha's footprints, and the dharma wheel.
This aniconism in relation to the image of the Buddha could be in conformity with an ancient Buddhist prohibition against showing the Buddha himself in human form, known from the Sarvastivada vinaya (rules of the early Buddhist school of the Sarvastivada):