 Nyāya and Vaiśeṣika atomists held that the world was created when order was imposed on pre-existing matter: the motion of atoms was ascribed to a divine source. Their analysis of motion and its causes employs concepts that have been compared to modern notions of force (Kumar 2019). Although the systems had naturalistic leanings, unusual motions such as the action of a magnet might be ascribed—as it was in the European middle ages—to the moral condition of human agents (Matilal 1977, 58). The organization of atoms was cited as a proof for the existence of God by the 11th century CE atomist Udayana (Gangopadhyaya 1980, 36). The mind and self or soul—like time and space—was regarded as a distinct category from material elements, a distinction traced back to the classical scriptures.