Morty is so dumb that...
1. He regularly disarms Rick's neutrino bombs. The first time he did it it was completely on the fly, no prior experience. Yet, he did it.
2. He has a knack for learning alien languages... as for the tree people in the battery dimension, it was obviously done without any sort of translator or support. (And he took over as their leader)
3. He's quick on his feet and can think his way out in a stressful situation, figuring out things that Rick can't and coming up with innovative solutions.
4. He figured out how to use a portal gun.
5. He can figure out how machines he's never seen nor used before work, and employ them successfully.
6. Beat Rick (smartest man in the universe?) in a board game.
7. Can manipulate said "smartest man in the universe", if he so chooses.
8. Became a successful stock broker. Out of the blue. Just did it.
9. Run. Whole. Freaking. Civilizations (and also toppled them as Marta)
10. Pitches good ideas that Rick typically ignores
11. When suddenly becomes motivated to try, he is good at math
12. His ideas were good enough that he would have gotten a deal for a movie production...!
13. His default intelligence is maxed out.
...At this point, it's only a matter of time before he starts making his own inventions, Eyepatch-Morty-style.
GUYS.
The only reason we've been thinking that Morty is stupid is that Rick has been calling him stupid repeatedly.
Sure, Morty does plenty of dumb stuff, but so does Rick. Rick has the emotional intelligence of a four year old and throws tantrums of cosmic proportions whenever slighted (vat of acid? submit to the selfie?), while often going ahead with complicated, innovative ideas... that in reality solve nothing and are a waste of time (Pickle Rick?? Leg Rick?? Cloning his own daughter? The dumb time-loop in his own dimension? Replacing himself with a robot? Creating a robot ghost to scary Mr Poopybutthole instead of just telling him to leave??) Not to mention his many incredibly lame jokes.
Everyone does dumb stuff occasionally!!! No one is an impeccable genius of non-stop moments of brightness!! (even Eyepatch Morty, the most cautious character, the character who has made basically NO MISTAKES up to now, sounds dumb a couple of times: "I'm gonna do the thing I wanna do, with the curve thing" and "My biggest fear is other people being afraid. Of fear. Itself." lol).
If Rick hadn't been calling Morty a freaking idiot with every breath available, we wouldn't be thinking "oh look haha the moron became a stock broker, what a joke, must be some sort of fluke"; we would be thinking "what an incredibly gifted kid".
We would attribute Morty's many mistakes to lack of experience, to lack of wisdom, to youth, to enthusiasm, to idealism, to teenager hormones, to acting hastily.
We would wish to see him eventually mature, apply his time and effort to worthwhile endeavors instead (mainly) of inane teenage stuff. We would wish to see him do well in school, we would wish to see him reach his full potential and succeed in great things.
Only Rick keeps pounding our heads with how stupid Morty is, and all of Morty's successes are never mentioned again, but getting lost to oblivion in comparison to Rick's (who has 60+ years more experience) genius.
WE VIEWERS ARE BEING UNWITTINGLY MANIPULATED THE EXACT SAME WAY MORTY IS.
Edit: This is by far my most popular post, so if you find my thoughts at all valuable, I'll hitchhike a message here:
I'm dropping Rick and Morty. For good. S09E01 was absolutely the worst thing the showrunners could have created: in season 1 Eyepatch Morty strapped boys down naked and tortured them; in real life he would be a prime suspect of having gone through CSA. Then in S09E01 they had him happily say incest jokes about himself and his abuser, and Rick responding by proudly declaring himself irresistible. No other character challenged this. It was a pedophile's wet dream.
We are expected to agree and laugh along, because we, along with Morty, have been groomed into accepting Rick (and the show) as flawed but inherently benevolent with juuust enough good qualities that later get backtracked. Rick is bad, sure, but ayone who could challenge Rick or be an alternative companion for Morty turns inexplicably monstrous, painting Rick in a positive light by comparison, and as the best option for Morty. Actual resolution for Morty's torment is not an option, since the showrunners want the show to go on forever.
The show isn't about abuse; the show is abusive. And it is grooming US into accepting an extremely toxic narrative.
I have no interest in watching such a show.
