The amount of glossing over linguistics in Project Hail Mary does make me a little crazyyyyyy because even on Earth it takes months/years for people to build up fluency in another language. And even if we are just focusing on the translation dictionary, so just very simple word to word correspondences, it's still crazyyyyy that they are able to get 250+ words in a matter of days including abstract words. Especially since they have completely incompatible nonverbal body language! Auggggh
Anyways my headcanons I am Coping with:
Ryland is actually kind of a savant for language learning but he's an amnesiac so he doesn't know and even before that was genuinely "What, like it's hard?" about it. Like he secretly has an incredible ear for language, but he thinks humans evolved to learn language and everyone could do what he can if they tried but they just don't care. He can pick up the basics of languages and accents in a matter of days/weeks for fun, and was an absolute menace in grad school and during the "living on a big international scientific collaboration boat" phase of the project because absolutely no language was safe to gossip in, if you had tea he WOULD figure out what language you were kiki'ing in and start listening intently and teaching himself it from context clues and spring it on you when you least expected it
They are actually not that good at language learning and made a large number of incorrect assumptions at the start, and have learned a number of things completely wrong. BUT Rocky's memory means he remembers what all the wrong words are and he's like "Whatever, it's easier to use west for left then to correct the leaky alien" of whatever.
Building on previous idea, especially once Grace becomes confident in his ability to recognize Eridian words and is less reliant on his translation program- they are engaging in true freak2freak communication and are using extremely impressionistic vague meaningless language with each other but are such mathpilled science geeks that they can intuit what the other means because they are so good at engineering. Like they are sort of using each other as Ouija boards, they know what SHOULD come next as they're problem solving so they 'hear' the other say it regardless of what's actually being said
Like it makes a group of Eridian linguists absolutely apoplectic to listen to a recording of Grace and Rocky problem solving together and it's just them speaking in nonsense words and sentence fragments punctuated with math. Like 30 minutes of "And what if we...question?" "Oooh you could!" "And then-" "Exactlyyyyyy" "Amaze amaze" "Grace and Rocky save stars 🥰" "Yes yes yes 🥰" and the Eridian linguists are like HOW. Did you possibly save two worlds. While communicating like THAT. QUESTION!?
The running theory among Eridian linguists is that humans' ability to perceive electromagnetic radiation gives them mild psychic abilities and that's how Grace was able to intuit the meaning of multiple abstract words. He denies it but they absolutely don't believe him. His insistence that somethings just have 'a vibe' in particular seems suspiciously psychic to them.


















