Neoplatonism is a philosophical system that emerged in the 3rd century CE, primarily associated with the teachings of the philosopher Plotinus. It builds upon Plato's ideas, emphasizing the existence of a single, transcendent source of all reality called the One or the Good, from which emanates a hierarchy of being, including the Intellect and the Soul. Neoplatonism integrates metaphysical and mystical elements, influencing later Christian, Islamic, and Jewish thought. Its core themes include the pursuit of spiritual knowledge and the idea of returning to the divine source through contemplation and intellectual insight.