[Alcuin]

Arthur C. Clarke wrote the script of 2001: A Space Odyssey with filmmaker Stanley Kubrick; he also invented the geostationary satellite, such as weather (and spy) satellites.

Clarke’s third law,

Any sufficiently advanced technology is indistinguishable from magic.

sounds a lot like the confusion of Elves and Men over what Tolkien called magia versus goeteia in Letter 155 to Naomi Mitchison.
Wikipedia notes that Clark’s third law sounds a lot like American author Leigh Brackett in a short story, “The Sorcerer of Rhiannon", published in Astounding Science-Fiction, February 1942, p. 39 (I cannot find the context, nor have I read the story):

Witchcraft to the ignorant, … simple science to the learned.

Wikipedia also notes that during the Second World War, Clarke, who was British, had copies of Astounding smuggled to him by a friend because the British Government had banned their importation at the beginning of the war to make more room for food and munitions aboard ship.

Clarke served in the RAF in England during World War II. I do not know if he had any association with Tolkien; but perhaps there were friends in common. (Christopher Tolkien also served in the RAF, but in South Africa.) Whether or not this is so, I don’t think the observation that technology appeared to be “magic” was particularly novel: Edison and Tesla were both referred to as “magicians”.

Think about the technology we use every day. The internet, for one: that would look like magic to our not-so-distant forbears. Radio and television were referred to as magic: I still recall 1960s TV announcers proclaiming “the magic of television”, and I remember my mother (in the United States) weeping during the 1965 funeral of Winston Churchill, which was broadcast from London by satellite: magic. Things we consider “simple” – electric lights, air conditioners, medicines, chemistry, metallurgy, much less automobiles and airplanes and submarines and spacecraft – all things our ancestors of just a century or two ago could easily be convinced were “magic”.

Some of you may be too young to remember Teenage Mutant Ninja Turtles III, where Leonardo, Donatello, Michelangelo and Raphael are teleported back to early seventeenth-century Japan along with April O’Neill. April has a Sony Walkman with her: she’s captive in the castle of the evil Lord Norinaga when her walkman starts playing. Lord Norinaga and his guards jump back in fear, and April tells the English pirate in Norinaga’s court, Captain Walker, that she’s a witch, shrank five musicians, and imprisoned them in the little box; whereupon Norinaga has the guards chop the thing into pieces.

Tolkien said several times that the over-arching theme in Lord of the Rings is death. The theme is interwoven throughout the long tale from the Silmarillion onwards: the Elves have the life of Arda: to Men, they seem immortal. In fact, as Finrod reveals to Andreth (“Debate of Finrod and Andreth”, Morgoth’s Ring), at the end of Arda, Elves, too, die. He says Elves have heard of no hope of life beyond Arda, not even from the Valar whom they knew personally; while Men have the “Old Hope”, and as Aragorn told a grieving Arwen, “We are not bound for ever to the circles of the world, and beyond them is more than memory.”

In Letters 212, Tolkien wrote,

To attempt by device or “magic” to recover longevity is thus a supreme folly and wickedness of “mortals”. Longevity or counterfeit “immortality” (true immortality is beyond Ea) is the chief bait of Sauron – it leads the small to a Gollum, and the great to a Ringwraith.

And in the long Letter 131 (to Milton Waldman), he said,

[The Elves] wanted to have their cake without eating it. They wanted the peace and bliss and perfect memory of “The West”, and yet to remain on the ordinary earth where their prestige as the highest people, above wild Elves, dwarves, and Men, was greater than at the bottom of the hierarchy of Valinor. They thus became obsessed with “fading”, the mode in which the changes of time … was perceived by them. They became sad, ... and their efforts all really a kind of embalming…

…At Eregion great work began – and the Elves came their nearest to falling to “magic” and machinery. With the aid of Sauron’s lore they made Rings of Power…

The chief power (of all the rings alike) was the prevention or slowing of decay (i.e. “change” viewed as a regrettable thing), the preservation of what is desired or loved, or its semblance – this is more or less an Elvish motive. But also they enhanced the natural powers of a possessor – thus approaching “magic”, a motive easily corruptible into evil, a lust for domination.

Elves don’t want change: hence the Rings of Power. Men don’t want change, either: they fall to fear of death, envy the Elves, and the Númenóreans launch an quixotic assault upon Valinor, ending with not only the destruction of the invading armada, but the destruction of their island and a collapse of their civilization. Though they revived in the northwest of Middle-earth (Arnor and Gondor), they never overcame their fear of death, and continued to engage in futile attempts to prolong their lives.

Finrod told Andreth that for Elves,

Our hunter is slow-footed, but he never loses the trail. Beyond the day when he shall blow the mort, we have no certainty, no knowledge. And no one speaks to us of hope. … And yet at least ours is slow-footed, you would say? … True. But it is not clear that a foreseen doom long delayed is in all ways a lighter burden than one that comes soon.

I think the intent behind Tolkien’s work is the languages he created: every language needs a speaker, and the speaker needs a story. For Tolkien the philologist, how the speakers of his language perceive life and death is important to knowing how the language will change. That both longevial Elves and short-lived Men speak the same tongue, living together and witnessing the outcomes of one another’s lives and modes of living, also affects the language. Death in the near-term, opposed to hope in the long-run, is what divides the two groups; otherwise, they would be mostly indistinguishable.