An Eldritch Language

Two things are at part of the heart of Lovecraftian cosmic horror: the powerlessness of humans before supernatural and natural phenomena on a superhuman scale, such as the grand creatures of Lovecraftian lore, and the possibility that there is no such thing as objective meaning to human life.  Everything from the extreme physical abnormality, size, and power (compared to what is regularly seen in ordinary life) of the extraterrestrials like Cthulhu to the metaphysical ability of the deity Azathoth to unintentionally create a cosmos while asleep to the madness that befalls some of the humans who learn of these things is all to emphasize how terrifying knowledge of reality can be, as well as how small humans can feel.  The now somewhat mainstream Lovecraftian style of monster is only meant, when handled in the true spirit of Lovecraft, to provoke existential terror about epistemology and metaphysics--or to give someone a way to focus on existential fears they already have as they read stories and reflect on them.

The tentacled face of the "Great Dreamer," otherwise called the Great Old One Cthulhu, is but one of many ways that the physical bodies or the chosen physical forms of these entities reflects this vast difference between humans and the Great Old Ones or the Outer Gods (of which only one seems to truly be a deity).  Cosmic horror on both an ideological and artistic level is at least meant to instill a sense of being but a small creature in a vast universe--the vastness of the universe in truth having almost no philosophical significance in itself but still a useful artistic theme--and a universe that is ultimately inhabited or observed by incredible supernatural and extraterrestrial beings with their own wars, goals, and philosophical awareness or stances at that.  Humans epistemological limitations, the breaking point of individual protagonists past which they go "mad," and the potentially terrifying aspects of reality are some of the attached themes.

Matching the physical abnormality and extensive power of some of the Lovecraftian entities is the language of these eldritch creatures, such as the R'leyhian language spoken by Cthulhu.  Even more contemporary cosmic horror stories inspired by Lovecraft's ideas such as the multiplatform video game Call of Cthulhu and the indie game Omen Exitio: Plague feature sentences written in eldritch language.  While the language appears as random letters or other symbols that do not resemble the protagonist's usual language of English, it expresses the thoughts of these ancient beings that are usually kept secret from humanity.  The language of these sometimes mostly supernatural and sometimes more physically monstrous beings expresses just how utterly foreign they are to humans.  If something as relatively trivial as the words and symbols they use to communicate things are bizarre and alien, then their goals and behaviors are only moreso "alien" in ways beyond these creatures coming from other planets or dimensions.

At the same time, there are demonstrable philosophical facts that could not be true even in a Lovecraftian cosmos where the entirely of the physical world and the humans that live in it are the product of the blind power of Azathoth--at least according to popular representations of this universe.  A core one is that even Azathoth or any other true deity cannot have brought logical axioms and whatever logically follows from them into existence; that which is true by necessity cannot have not existed, cannot be dismissed from existence, or changed in any way.  Whether or not Lovecraft intended for this to be denied in his works, a true logical impossibility like this can at most be denied by characters or lied about by third-person "omniscient narrator" language.  The non-truth of logical necessities is just as impossible in a work of fiction, even a work of fiction by Lovecraft, as it is in any other aspect of reality.  There are also truths about language that could not be false even if an eldritch being like Cthulhu was to utter them.

No one needs words to grasp the laws of logic: they are true by necessity, after all, and thus both metaphysically and epistemologically precede language.  Language can only be created because it is logically possible and can only be understood as a philosophical, communicative method because of logic.  All words one could conceive of, all words that could be contrived are nothing more than possible but somewhat random ways to communicate truths, concepts, and experiences.  In a very secondary sense, language can also help people focus on and think about certain issues as they reflect outside of interpersonal communication.  Still, words are not the truths they describe and every individual word assigned to an idea could have had different lettering or a different sound.  Never is language anything more than this, a tool needed only by non-telepathic beings to communicate precise ideas.

The same would be true of an eldritch language.  Not even seeing a Great Old One, perhaps Cthulhu ascending from the sunken city of R'yleh, is something that there are no truths about, as all things are governed by logical axioms like that something must be true and that it is impossible for something that logically follows from another thing to be false, and since logic can be grasped without language to guide thoughts towards it, seeing a Great Old One could be understood without the assistance of human or eldritch language.  It is not just some truths that transcend language.  All truths do.  This, like the necessary truths of logical axioms, is the case in fiction as well as everything else.  What is supposed to help convey the differences between Lovecraftian entities and humanity is at the same time ultimately a similarity between humans and the beings like Cthulhu.  An eldritch language would is not necessary unless these creatures need to communicate non-telepathically or choose to conjure up words of their own anyway, something humans also have the capacity for.