Mercerism is a new religion based on the life and teachings of Wilbur Mercer. It's spread all over Earth and in the space colonies, thanks to some mysteriously-appearing empathy boxes that showed up after Mercer's death. Mercerists follow two major tenets: (1) be empathic to the individual and (2) work for the good of the community. And rather than going to a church or temple to worship, Mercer's followers use a device—the empathy box. Gripping the twin handles of the empathy box, users enter a parallel world, or perhaps a shared hallucination, where everyone is connected together within Mercer's mind. Everyone takes place in the ritual together, a collective consciousness all crammed into Mercer's head. Empathy leads to a sense of community; community leads to empathy. Mercerism exists to show "that you aren't alone. I am here with you and always will be. Go and do your task, even though you know it's wrong". Too bad Mercer is later revealed to be a fake.
One of the weirder parts of the Mercer mythos is the importance of the donkey and the toad, "the creatures most important to him." These might be pretty ordinary animals, but in the future, they've all vanished, "become extinct" thanks to the nuclear war. Donkeys are known for being creatures that were domesticated by humans to do difficult jobs for them. They pack heavy loads, pull the plough, and can even be ridden to get to certain points. Toads are highly adaptable, as they live part of their lives in the water, part on land, and all across the world—though some of them probably shouldn't have ended up in Australia. Based on these characterizations, these animals are most likely special to Mercer because they symbolize humanity. Humans are highly adaptable; in the novel they even moved into outer space. Yet they also have to suffer and work hard to survive in this world.
Each android character brings new concepts of what it means to be an artificially created human, and the meaning the androids can change depending on the theme. In the future society the androids are viewed as "alien" and "dehumanized". First, they're illegal aliens, having fled a life of unequal hardship and endless work. (They're also real aliens, since they come from Mars.) Second, they aren't considered human by the standards of the society they live in. Rather, they are considered property, a product created to make life easier for the space colonist in the same way a dishwasher or washing machine makes our lives easier today. The android's designed to do people's work for them without any gain of its own. Like the slaves sold in Brazil, the Caribbean, and the Southern States, the androids fall under what is often termed chattel slavery. Also, like the slaves in American history, the androids were created for the sake of profit. The profiteers in this future society are mega-corporations. In the case of the Nexus-6 androids, it is the Rosen Association. After Rick gives Rachael Rosen the Voigt-Kampff test, he realizes Rachael and Eldon can't afford the luxury of being individuals. Everything they do's for the corporation, and they themselves had become dehumanized.
After World War Terminus, the world became a mess, to say the least. Entire cities were destroyed, large swaths of wilderness were wiped out, and entire animal species died thanks to radiation-laden dust in the wind. This disaster led to animals needing to be cared for by humans if their species were to survive. Citizens of future earth had to care for animals how and where they could, whether in their apartments or on their rooftops. The animals represent regeneration, which makes them a type of anti-kipple. After the war, the people of Earth — as in, all of society — decided to care for the remaining animals to keep them from going extinct. They want to save what they can from the old world and maybe even return things to the way they were one day (… as unlikely as it sounds). Animals aren't just a symbol for the reader; the characters in the story see them symbolically, too—at least in their hallucinations. After the spider has its legs removed by Pris, Isidore tries to drown it in the sink. The trauma pushes him into a hallucination where he meets Mercer, who hands him the spider "with its snipped-off legs restored". For Rick and Bill, owning an animal is about more than the social good; it's about increasing their social status. As for electric animals, Rick initially thinks they're not worth saving, and not a part of society's push toward regeneration, though he changes his tune upon realizing it can still keep the memory of the animal alive for people.
The Voigt-Kampff test is the standard for differentiating androids from humans. During the test, the test giver, usually a bounty hunter, asks a series of questions revolving around hypothetical social situations where an animal is harmed or killed. The test giver then reads the taker's reaction to the question. If the taker shows an empathic response to that poor lobster's fate, he or she is a human and could walk free. But if no empathic response is shown, he or she is an android and would be killed. But there are a few problems with the Voigt-Kampff test: 1) a human with an "underdeveloped empathic ability" might be killed in place of an android, 2) the test generally looks for a person's empathic response toward animals. This means there can be holes in a person's empathy, but as long as that hole doesn't deal with the animals in question, the person will pass the test, and 3) a lot of people would fail the test as while the fates of the animals are horrible, but several of the situations are so commonplace to us that we in fact don't think of them as horrible. The Voigt-Kampff test symbolizes laws created throughout history that separate "us" from "them," and tests that help "us" rise above "them."
Penfield Mood Organs are devices used by future citizens to regulate their emotions. They just need to find the proper emotion number in the manual, dial it, and then they get to feel whatever they want. For example, if they input 481, they instantly receive an "'[a]wareness of the manifold possibilities open to [them] in the future'". The problem with the Penfield, according to Iran, is that people live with the absence of appropriate affect. Also known as the flat affect, this is the condition where "a person does not display emotions to the degree that other members of his or her culture normally exhibit". It's actually not that different from being an emotionless android.
Kipple is everywhere, because it's the representation of decay and degeneration in physical form. In the book, it's really everywhere. World War Terminus has left our home planet in an awful mess: entire cities have been leveled, radioactive dust is getting in everyone's hair, and people have left the planet to go seek a new existence in the space colonies—leaving behind all their stuff. As that stuff rots and decays, it becomes kipple. People experience the disrepair of consumer goods in our everyday lives. Anyone who's ever maintained an attic, rented out a storage unit, or had a locker can tell you how true this is. As we collect stuff, and the stuff just spreads out, growing in number, expanding the mess as it goes, bringing disarray into our lives with a tsunami of junk.
Dr. Eldon Tyrell lives in a penthouse at the top of a giant pyramid, which is also the headquarters of the Tyrell Corporation, the company responsible for the replicants. Although the pyramid's more like a Babylonian ziggurat. This gives us a good idea of the kind of person Tyrell is and that he has the position and authority of a king or even a god. For Roy and the other replicants, Tyrell basically is a god, being their creator. Plus, in Babylonian mythology, the gods created human beings essentially to serve as slave labor to provide the gods with food in the form of sacrifices—they didn't love humans or intend to reward them in heaven. That's basically how Tyrell views his replicants: as just part of his business, a device to make money for him.
When Deckard pursues the replicant Zhora, a snake scale he finds in a drain eventually leads him to a cabaret where he finds her performing a seductive dance with a snake. (not a real snake: since so many animals have died out, rather a replicant serpent itself.) Zhora herself has a snake tattoo on her neck. It's possible the snake fits in with the mythological and biblical echoes in Blade Runner, along with the pyramid or ziggurat where Tyrell lives and the "Methuselah syndrome" from which Sebastian suffers. When an unseen emcee introduces Zhora at the club, he makes reference to "the serpent that once corrupted man." Everyone in the film has to live in a corrupt society, with greedy, amoral people and the replicants suffering the worst.
There's an owl in Tyrell's penthouse, though it's not a natural one. Like the replicants, it's artificial, even if it is an exact copy. In the novel the film's based on, owls are the first creatures to go extinct when nearly all animal life dies out on earth. So that might be a reason for the presence of the owl in Tyrell's office (Tyrell also has a statue of an owl). Plus, the owl is a famous symbol of wisdom and knowledge. Tyrell, after all, possesses the secret, genetic knowledge that has allowed him to become a corporate overlord and creator of replicants. At the same time, the owl is famously considered a bird of ill-omen in many cultures throughout the world—which hints at both the wickedness of Tyrell and his impending death at Roy's hands.
Leon and Rachael both have fake family pictures to go along with their fake implanted memories… maybe Deckard does as well. In Rachael's case, her memories and her pictures were actually copied from those of Tyrell's niece. As Tyrell explains, the memories help provide an emotional "cushion" for the replicants—instead of acting really weird, and having strange reactions and off-key ways of expressing empathy, the memories allow the replicants to behave in a more fully human manner. It also begs the question, if memories help determine what a person really is, then who's someone who has entirely fake memories? Does Rachael really have a self of her own, or has it just been borrowed from the woman who's memories she now possesses? Interestingly, when Roy comes to die, his final words have him cherishes his memories — and not apparently fake ones either. He remembers moments from his real life, engaging in combat missions on the Off-World colonies. In this way, he's affirming his own authentic identity, even as it slips away from him in death. At the same time, by demonstrating real empathy and allowing Deckard to live, Roy is asserting his true humanity against the forces that have tried to make him nothing but a killer and a slave.
While Deckard and Gaff are investigating Leon's apartment, Gaff creates a little stick figure out of some matchsticks and leaves it seated on a table. It's a symbol — and perhaps a clue to Deckard. The replicants themselves are like matchstick men (or women): they're made to be disposed, having a four-year life span. Gaff might just create the figure out of restlessness, but in the movie, it serves symbolic values.
The unicorn only appears in the Director's or Final Cut, but original as an origami unicorn that Gaff leaves for Deckard to find at the end of the movie. In the middle of the movie, Deckard gets drunk and looks at family pictures while sitting by the piano in his apartment, the later versions reveal that there was actually a brief dream sequence at this moment, in which Deckard sees a running unicorn. The fact that Gaff then leaves behind a silver origami unicorn is meant to the indicate that he knows Deckard's dream, indicating that those dreams were perhaps implanted, just like Rachael's memories… which would mean that Deckard could actually be a replicant.
Eyes are very common in the film. There's the fake lenses shining in the eyes of the replicants — and in the eyes of an artificial owl; the hellish L.A. landscape reflected in an eye; and Roy and Leon taking a trip to the lab of a man who designs eyes (and who made their eyes, specifically). Maybe the reason eyes come up so frequently is because they're traditionally thought to be the "windows to the soul". Whereas the humans treat the replicants as though they were just machines or tools, which can be "retired" without ethical compunction, they actually experience reality in a rich and conscious way — their eyes aren't empty. When Roy talks about the things he's seen with the eyes Chew has manufactured, he's really talking about how astounding his experiences have been, and he's denying the notion that he's just some lifeless automaton.
When Roy and Leon arrive at the eye lab run by Hannibal Chew, Roy misquotes the famous British poet and visionary William Blake: "Fiery the angels fell; deep thunder rolled around their shores; burning with the fires of Orc." (In Blake's actual quote the angels rise from the fires of Orc rather than fall.) By identifying with these fallen angels, Roy says something about himself—he's a rebel. And he's rebelling against the state of things in a fundamental way, challenging the man who created him, Dr. Tyrell, just as some of the angels rebelled against God. But even though Roy identifies with the fallen angels and kills his own creator, he ends up assuming Christ-like symbolism at the end of the movie. He goes from being a guy who wants to upset the status quo to a guy who accepts his own mortality and suffers for it in a redemptive fashion. He's also angelic in the sense that he has powers and abilities that go beyond the human—Roy's not so much an inhuman robot as he is a superhuman, a person who's passion for life is transcendent.
When Pris and Roy seek out the genetic designer J. F. Sebastian, they discover that he has a glandular condition called "Methuselah Syndrome," which causes him to age prematurely. Naturally, they see that he's in the same boat as they are — since they also have a set time limit on their lifespans — and they try to leverage that for aid and empathy. Sebastian ends up helping them, though probably more out of fear than anything else. It doesn't work out well for him as Roy kills him off-screen. The fact that Sebastian's disease is called "Methuselah Syndrome" fits in with some of the biblical echoes in Blade Runner, since Methuselah is the character in the Hebrew Bible who is said to have lived the longest, hitting the ripe old age of 969, so it's also a case of Ironic Name.
At the end of the movie, Roy Batty goes from being an Ax-Crazy maniac to being a Christ-figure. He pushes a symbolic nail through one of his hands before sparing Rick Deckard's life, and then he dies due to his expired time limit. In the voiceover to the original version of the movie, Deckard provides a hint of Roy's motives: loving life more than he ever had before. At the end of the movie, Roy Batty goes from being an apparently haywire maniac to being a Christ-figure. He pushes a symbolic nail through one of his hands before sparing Rick Deckard's life, and then he dies due to his expired time limit. Batty is a victim of society, created to be a slave and doomed to die at a set time. He initally responds to the injustice of his condition by seeking out the people who created him and killing them when they can't expand his life. He also breaks two of Deckard's fingers as punishment for killing Pris and Zhora — which is reasonable, but not something Jesus would have done. But when it comes time for Roy to die, he flips out and drives a nail through his hand. After this, he achieves the fullest expression of his humanity by letting a dove go and showing mercy towards Deckard. Symbolically, the nail may represent all the suffering and the difficulty he's gone through in his life. Ultimately, those things have taught him compassion instead of just making him an unreflective killer, and this is what allows him to save Deckard's life as the movie comes to an end. The dove is a traditional image of the spirit or the soul — which is something that the replicants aren't supposed to have. They're just meant to be tools or objects, according to the company that made them. But Roy manages to contradict the Tyrell Corporation by demonstrating he has a soul by showing mercy towards Deckard and refusing to kill him. Then, as he dies, he releases a white dove he's been holding. It soars into the sky like his soul rising into heaven.
Movie geeks are still debating over whether or not Deckard's human or a Replicant to which the movie never provides a definitive answer. The theatrical release seems to confirm that Deckard's birth didn't involve a bar code scan. Key scenes are cut and subtle clues simply don't show up. You can make the assumption that he's a Replicant, but there's not a lot of evidence to back you up. But, with the various director's cut versions, the question gets a whole lot trickier, and some very tasty clues crop up to suggest that Deckard is also a product of the Tyrell Corporation such as glowing eyes (like the other replicants), the fact that he's a lot more attractive and not physically damaged like most of the humans, not to mention the aforementioned unicorn dream... or simply Wordof God.
K finds Deckard in a city that has been turned to orange ash after the nuclear war. This dystopian desert is a symbol of how all great structures built by man are hollow and lifeless in the reality of war. They no longer hold value as they can no longer harbor life.
K is approached by the beautiful hologram he keeps with him that tells him he is lonely. In this advanced and "sophisticated" world full of every choice imaginable, we see that this is a symbol of the lack of true connection in the world. We will always be lonely when we are removed from truly connected with another human being.
K is a replicant tasked with destroying rogue replicants. This is a symbol of how man turns one against its own in order to maintain power for the select few. K represents that many who make their survival by doing things for an establishment they don't believe in, because without doing this work they wouldn't have the means to survive.
Throughout the film we learn more about the ability for a replicant to reproduce life rather than be created. Deckard and Rachael having a child is a symbol of the ability for replicants to reproduce, something that has never happened before. And Wallace wants to harness this power in order to populate worlds and expand his power.
Wallace offers Deckard a clone of Rachael in exchange for all that he knows. Deckard refuses and Wallace destroys the clone. This is a symbol that what Wallace was offering Deckard was never going to be his. It's Wallace's way of showing that he controls life, he gives it and takes it.
The birth records contain entries for a girl and a boy with identical genomes, and the girl was said to have died of "Galatians syndrome". Galatians is the book of the New Testament where St. Paul says Jewish law doesn't apply to Gentiles who convert to Christianity. The records were falsified by the Replicant resistance, who want to prove that laws restricting Replicants don't apply to a child born of a Replicant.
When Dr. Ana Stelline is introduced, she is in her own forest world (it is probably the only time in the movie green fills such a large part of the screen, making it feel jarring and unexpected), focusing on morphing a beetle (considered by some to be a reference to The Metamorphosis by Kafka and heavily dissected by Nabokov, two recurring literary author references found in the script). The real people outside cannot see anymore forests because all the forests died, yet she can still create an artificial forest in her enclosure. At the ending, when the real world outside snows, Stelline is creating her own snow inside her enclosure. As K, an artificially created human experiences the real snow, Stelline, a human born of an artificial replicant, experiences the real things through her own artificial creations.
Also in that scene; when we see K from Ana's perspective as she views his memory, her reflection is on top of him. When we see her from his perspective, he's a shadow looking over her shoulder. Turns out she put her memories into him, and he's a reflection, a shadow, only viewing those memories secondhand. There's also shots in the scene while they're both standing, and Ana's "inside" Kay.
K finds a colony of living bees in a nuclear wasteland on an even more wasted earth where all the flowers died. The director stated that bees symbolize hope in a dying world, living on. They also have many parallels to replicants, given that they live in individual cells and an entire colony is born from one mother like all replicants having a single source.
When Gaff presents the sheep origami to K, Gaff is playing a game of Nine Men's Morris. During the scene, Gaff wears white and K wears black, representing the two sides, and white is losing, and it mirrors the games of chess in the original Blade Runner.
A lone dead tree on Sapper Morton's farm held up by wires represents both life and death. Trees are very rare in 2049, and this lone dead tree is a beacon of the remnants of life in the dystopic world. It is where the dead pregnant replicant was buried, and where K begins his investigations that would eventually lead him onto a road of self-discovery.
The inexplicable and gigantic erotic statues of naked women in Las Vegas symbolize hedonism to the extreme. Their current desolation in a wasteland mirrors how human excess had drowned itself with waste.
Deckard keeps a dog that he doesn't know if is real or not. Considering that the pollution has gotten so bad it apparently wiped out most non-human animals as well, including dogs, Deckard's dog symbolizes the Ambiguously Human nature of the replicants and their status in a world where humanity has declined.
When K decides to save Deckard, he's standing in the rain. It's a sort of baptism, and he becomes a new man by rejecting Joi's worldly temptation. Then he saves Deckard by drowning Luv, symbolically killing someone who represents his old self, a slave to the system. Both he and Deckard emerge from the water as new men. They're also possibly free because it might look like Deckard died.
In the first film, the Tyrell Corp ziggurat/pyramid symbolized the company's godlike power, and Tyrell's own G/godlike role. In the second film, Wallace clearly has a god complex. His HQ makes the old Tyrell place next door look like a stepstool, and pokes above the clouds like the Tower of Babel. Tells you something about his ego.
In the opening sequence, K says he "prefers to keep an empty stomach until the hard part of the day is done". The camera cuts to a shot of a bubbling pot. Lot of heat, small space, contents under pressure, eh?
In the scrapyard, the scavs bring down K with a spear, a net, a kite, and lightning. This references fishing, the force of nature, and Ben Franklin's electrical experiments, which is ironic for such low-tech people attacking a high-tech vehicle (and two more high-tech Wallace products). Luv saves Kay by dropping some kind of Wallace Corp air- or orbital strike on the scavengers. She also tells K to "Get up" and do his job. Now, what delivers "God's" wrath on the unworthy in the Bible, and encourages His servants? Oh, right, angels.
There's a shot in the scene where Joi desperately tries to wake up K, but her projector is glitching, she can't make a sound, and, obviously, can't touch him. Then she vanishes, revealing the very real, very physical scrappers coming to kill K. Force and humanity beat technology and illusion.
When Luv enters Joshi's office, she turns on the lights. She's an "angel" and servant who literally brings light and starts the movie wearing white, sins against her Creator, is a very good liar, and is jealous of his other creations. Like Lucifer.
In the first film, Tyrell wore glasses, which may symbolize his limited "vision". Wallace is completely blind, and his vision is even more limited.
Joshi's speech about the wall that separates kind is paid off later in the movie. To quote a Youtube comment;
The city represents something man-made (replicant) and the ocean represents something natural (human). Notice when K and Joi go to the Trash Mesa, K is flying the spinner close to the wall, on the city side. During the climax, Joe flies over the wall. This means he is turning human. He proves his agency by disobeying the orders of Joshi for self-preservation, and also disobeying the orders of the rebel leader for self-actualization. The idea to rescue Deckard and take him to his daughter is his idea, brought into reality by consciousness.
; when we see K from Ana's perspective as she views his memory, her reflection is on top of him. When we see her from his perspective, he's a shadow looking over her shoulder. Turns out she put her memories into him, and he's a reflection, a shadow, only viewing those memories secondhand. There's also shots in the scene while they're both standing, and Ana's "inside" Kay