Unlike in Classical Greece, Egyptian cosmological, metaphysical and ethical concepts did not crystallize over the course of a few centuries. Instead they were the outcome of millennia of intellectual labour, during which hundreds of priests developed and grappled with challenging, often contradictory, ways of making sense of the universe. As part of that process, several schools of religious thought emerged, occasionally competing to establish their respective deities as the supreme creator. This jostling inadvertently ignited several intellectual breakthroughs at the end of the second millennium BCE, which resulted in Egyptians advancing ideas remarkably similar to some of the mainstays of later Hellenic and Hellenistic thought.
In ‘Theological Responses to Amarna’ (2004), German Egyptological heavyweight Jan Assmann showed how the process began in the fourteenth century BCE when Akhenaten ascended to the throne. He sought to dismantle the powerful religious establishment that stood in the way of his quest for absolute power by using a proto-scientific worldview to eradicate Egypt’s polytheism. That is, he banned the entire Egyptian pantheon and replaced it with a single figure: Aten, the personification of the disc of the sun, or of solar energy. Anticipating the earliest pre-Socratic thinkers, who in various ways traced the source of the cosmos to a single element, Akhenaten promulgated that solar energy was not only divine, it was the sole element out of which the entire universe evolved. Each component of visible reality was described as an ‘evolution’ or emanation of that energy. In turn, the realm of invisible deities, the underworld, and spirits, were dismissed as fairy tales from a bygone era. Temples were closed, inscriptions referencing other gods were erased, and even representations of other deities were destroyed. This was the first time in history that a form of monotheism had been adopted as the official creed of a kingdom.
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The priesthood answered Akhenaten’s monist challenge in a way that prefigured Hermetic, and perhaps even ancient Greek efforts, such as those of Parmenides and his followers, to uncover the oneness concealed behind the plurality of the visible world. The Egyptian priesthood revamped older ideas to posit a hidden divine entity, symbolized by the sun, as constituting and animating the universe. Struggling with the limited vocabulary of their time, priests tried alluding to this unknowable Supreme Being’s immaterial qualities by loosely naming it ‘One’, ‘hidden’, and ‘soul-like’. They claimed that it was inaccessible to language or intellect and inhabited a separate ontological space. Paradoxically, the same priests also averred that the millions of gods and other constituents of the universe were constantly evolving parts of this ineffable being, which remained present yet invisible in and as the cosmos. Egyptians occasionally used the word ‘Amun’ (‘the hidden’) as a pseudonym to refer to the nameless Supreme Being who was simultaneously a boundless unified hidden One and the infinite Many of the cosmos. This emphasis on the invisible and underlying ‘oneness’ of the visible universe may well have been a precursor to the Eleatic Greek idea that the manifold world of sense perception conceals or misrepresents true reality, which is singular, all-encompassing, omnipresent Being.
– Peter Flegel, ‘Does Western Philosophy have Egyptian Roots?’
Notes from a Room 