According to David Kalupahana, the Upanishads do not strictly distinguish between the two. In contrast, Damien Keown and Charles Prebish state the texts do distinctly present both the male deity Brahma and the abstract Brahman, however, in the Upanishads, deity Brahma is only referred to a few times. The Brahman as the eternal, absolute metaphysical reality – along with Atman (self, soul) – is the predominant and frequent teaching in the Upanishads and other Vedic literature of the Upanishadic period, so much so that early Hinduism is also referred to as Brahmanism. The Pāli scriptures, which were written centuries after the death of the Buddha (although understood as representing the memorized word of the Buddha), mention Brahma, but there is no unambiguous mention of the gender neuter Brahman concept.