It has been said that Newton was not the first scientist, but rather the last magickian. The bulk of his scholarly output was in fact occult & religious in nature; his interpretation of Biblical prophecy puts the end of the world at approximately 2060. One must appreciate the worldview of the 17th century mind; before, a world of chaos and disorder, ruled by mysterious forces beyond human comprehension - "gods". Thereafter, a world, a mechanism, obeying clear laws of nature, both intelligible to & exploitable by the human mind. "Any sufficiently advanced technology is indistinguishable from magic," as the famous saying goes, and this is the core idea of the magickal worldview - that through the application of one's mind alone, one can divine secrets of reality and even manipulate it towards one's own ends.
While the modern aesthetic is to use the framing & vocabulary of psychology - Jung declared in his "Psychology & Alchemy" that he had been accused of "psychologizing religion"⁰ - the fashion in the 17th century was to of course use the language of gods, angels, & demons, given the long-standing history of mythology & Christianity in Western academics, a tradition that ran all the way from Plato & Aristotle, dualism, the assertion of intellectual & archetypal worlds of forms, mathematical truths, logical necessities, and of cosmological arguments for the existence of "First Causes" that terminate an otherwise fallacious infinite regress; through Aquinas, who used these arguments to furnish theological proof for the Christian God, which then served as the metaphysical basis for the literati, which, in that era, was effectively coextensive with the clergy, the only people interested in reading texts often written in languages other than the vernacular.
Following the secularization of philosophy & academics, however, we have lost the cultural mindset and worldview that allows us to interpret classical texts speaking of "angels" and "demons" aright. Properly understood, these terms "merely" refer to thoughts and ideas, not metaphysical "energies" or bearded men in the clouds keeping the celestial spheres spinning by hand, like a cosmic micromanager. Since ideas are not embodied, almost by definition (c.f. Cartesian dualism & res extensa as contrasted with res cogitans), we necessarily must come up with fantastical and abstract imagery to represent the non-physical - everything from geometric Platonic solids, to mandalas, to winged humanoids. It is only the naive who take these images at face value.
Alternatively stated: gods, angels, & demons are only as "metaphysical" as thoughts & psychological patterns are, for they refer to the same things, merely with different words, vocabularies, & iconographies; hence Jung protesting of his charges of "psychologizing religion" - far from profaning the divine by reducing it to "mere" mundane natural philosophy, science & psychology, he was revealing the divine suffused throughout every moment of everyday experience in the self-evident existence of non-physical realities - thoughts, hopes, dreams, qualia - historically, "gods," as these things were once called, which participate not in Descartes' order of res extensa, entities with embodiment & physical extension, but of res cogitans - the order of mind.
And indeed, "order" and logic have both been central tenets of Christian and Western thought - the Logos, symbol of the intellect, basis of language, a fundamental and eternal principle against which all reality conforms, as surely and truely as 1+0=1. Hence the magickal worldview - exploring purely abstract realms of ideation reveals occult secrets of the physical universe that allow one to "hack the system" through cleverly designed exploits such as science and engineering, grounded by the pure, divine & abstract principles of mathematics.
"Magick is the Science and Art of causing Change to occur in conformity with Will."
- Aleister Crowley, "Magick in Theory & Practice."
P.S. on the nature & existence of thoughts, dreams, qualia - I do not deny the mind-brain connection, & the neurological reality that the mind & consciousness are rooted in & dependent on a physical substrate. One observation: Google Chrome, Facebook, are not written in binary, 100% of the features of the system implemented in manually entered 1's and 0's - the level of abstraction is too low to tersely describe the implementation, and hence higher level languages such as C, C++, JavaScript. Analogously, one would not give life advice or choose a life's calling in terms of action potentials & neurotransmitters - this vocabulary is too far removed from the human-scale problems & strategic quandaries that one is confronted with on a timescale of days, or years. Hence the two orders of body & mind, for when the emergent complexity of the latter exceeds the capacity for the vocabulary of the former to express things tersely and parsimoniously.
⁰ "Hence the universal depreciation of the soul in the West. Whoever speaks of the reality of the soul or psyche is accused of “psychologism.” The notion that there can be psychic factors which correspond to divine figures is regarded as a devaluation of the latter."