You know what makes people different from animals? We're the only species on Earth that observes Shark Week. Sharks don't even observe Shark Week; but we do. For the same reason, I can pick up this pencil, tell you its name is Steve, and then go like this; [snaps it in half; gasps of horror] and part of you dies, just a little bit on the inside. Because people can connect with anything. We can sympathise with a pencil, we can forgive a shark, and we can give Ben Affleck an Academy Award for Screenwriting. People can find the good in just about anything except themselves.
—Jeff Winger, Community.
Believe it or not, humans have an amazing ability to empathize with other humans and reasonably humanoid equivalents, even fictional ones! A lot of it has to do with the kind of focus a character receives, be it a Sympathetic POV, with Pet the Dog moments, or any of the dozens of Characterization Tropes.
This in turn extends a kind of Popularity Power onto the protagonist/focused on character, giving them a better chance of success in their endeavors than would otherwise be expected. So, one ninja can beat 10,000 other ninja because we've been following the one ninja the whole show; and we know nothing about any of the 10,000. On the other hand, when the villain comes, he's gonna put up an actual fight, because we know who he is, what he wants, and may even have developed sympathies for him as well.
The Rule of Empathy works hand in hand with Plot Armor; while the Rule of Empathy gives a greater chance of success Plot Armor makes surviving long enough to reach that goal easier. Interestingly, it is by no means linked to intelligence. A compassionate fool is likelier to survive than a pragmatic Jerkass. This is also why the Littlest Cancer Patient cannot die of anything but their illness, we're simply too attached to them.
Relatedly, it should be noted that the Rule of Empathy is not an all-powerful charm that grants success and survival to sympathetic characters. It may well be used against the characters/audience with the likes of a Mauve Shirt being Killed Off for Real, or to hook us into rooting for the Boring Failure Hero. As noted earlier, making a villain sympathetic is a sure way of making the audience deeply invested in a story. Sure, they're bad, but they're not all bad.
The Rule of Empathy also informs viewers and characters (and at times authors) just how good or bad an action is within the context of the story. When a villain destroys a whole Throwaway Country, we don't care because we never saw those characters. But when they kill one character the audience or hero empathizes with, then they've crossed the Moral Event Horizon.
The Rule of Empathy also has a dark side. There is a fate worse than being a "neutral" Innocent Bystander with no real attachment to the audience; characters who are notably unsympathetic will (with few exceptions) be in for a world of hurt. Whether it's because they Kick the Dog or do other heinous deeds that alienate them from (most) viewer's sympathies, these characters will have a comeuppance at the hands of something similar to karma, ranging from the Humiliation Conga, being Hoist by His Own Petard, suffering a Death by Irony, or falling to a Fate Worse Than Death. Related to Woobie and all variations thereof.
- An IKEA advertising campaign lampshaded this. One example showed a desk lamp being replaced and left out in the rain on the curbside. Cue sad music. The ad then proceeded to tell viewers they were crazy for having feelings for a lamp.
- Yu-Gi-Oh! (a series which, to most fans, thrives on Narm Charm) tends to get this a lot.
- We're given some particularly good reasons to empathise with Maximillion Crawford/Pegasus, who lost the woman he loved and has been trying to get her back ever since. Other villains such as Malik/Marik, who was forced into a role he didn't want to play his whole childhood and developed a huge bitterness towards the Pharaoh, Amelda/Alister, whose home country was destroyed by a war fought with weapons supplied by Kaiba Corp - you know, before Kaiba corp did games - and Bakura, whose entire village was slaughtered to create the Millennium items, also engender a lot of empathy.
- Then there's Yugi who is just... he's like the poster child for Woobification. If you watch the unknown first season in particular, or read the manga, then you see that he starts out as nothing more than a punchbag for every bully in Domino High. Including bullies whom he stands up for and who later end up being his best friends.
- If you don't give even the slightest a damn about the pharaoh after what happens to Yugi in the Orichalcos arc, then you have no soul.
- An interesting example is Rosa from Umineko no Naku Koro ni. Throughout the arcs, she tends to have one of the shortest lifespans of any of the characters, only once making it past the second twilight, and she often dies in very heinous and cruel ways. However, she just about never becomes The Woobie because the audience still holds a grudge against her for how she abuses her daughter, Maria. In a weird way, those two facts wind up sort of balancing each other out so that the audience can still hope that she eventually makes it out, but doesn't overly sympathize with her.
- The reason most of Kenji's gang and many minor characters in 20th Century Boys survived while more than 90% of the world's population was wiped out.
- In Fullmetal Alchemist, the Big Bad turns an entire Throwaway Country into Philosopher's Stones. This is upgraded from a terrifying display of power to an unforgivably evil act when we hear the voices of the souls of some of those people inside Hohenheim, and learn that they retained their consciousness and personalities even after being made into Philosopher's Stones. Their comments, especially their enthusiasm in using their souls to fuel Hohenheim's alchemy so he can defeat the Big Bad, make them sympathetic to the audience.
- In The Hunger Games, this is present as a part of the universe. When Haymitch is trying to mentor Katniss, he tries very hard to make her likable, to make her someone the audience will sympathize with. Sympathy will equal sponsors and money for necessities in the arena, and could therefore make the difference in the Games. Peeta, it turns out, is a natural at invoking the Rule of Empathy at the drop of a hat. Katniss is not.
- The Sisterhood of the Traveling Pants books by Fern Michaels: The author proves to have difficulty using this trope. The Vigilantes are a group of women who should have your sympathy, with their Dark and Troubled Pasts. Unfortunately, they prove to be politically incorrect, abusive to victims, sexist, acting more like Straw Feminists than real feminists, dishing out a Fate Worse Than Death than a Cool and Unusual Punishment, and acting more like spoiled little girls who have never really grown up than actual women. They basically get away with all of this because the author wants them to! It's no wonder other characters, including some of the villains, prove to be way more likable in comparison!
- Firefly: Don't hurt River or Kaylee. Everyone watching is their Papa Wolf or Mama Bear.
- Similarly, although Buffy the Vampire Slayer and Angel weren't afraid to kill off sympathetic characters, if Willow had died the fans would have burned the studio down. Fred is a borderline case because the actress continued on as Illyria.
- Common in Crime and Punishment Series. If she is pretty she didn't do it. This evidence is reinforced if she is slight of build and especially if they have a winning personality. She can never have done it.
- The Sarah Connor Chronicles: Cameron is a cold, emotionless, and literal killing machine who at one point leaves a man and his sister who helped her to die because they don't matter to her anymore. That doesn't change the fact that she is a deeply sympathetic character who rapidly obtained Ensemble Darkhorse Woobie status because of both how interesting she was and all the crap she puts up with without complaint for the Connors.
- Doctor Who pulls this all the freaking time, by introducing us to so many good natured, likable, honest folks, and then killing them in cold blood. Such as poor Mo in the episode Hungry Earth, who we first meet while trying to help his dyslexic son to read a book ("who loves you more than me?"). He survives, but he does end up being kidnapped and vivisected.
- Please direct your attention to the Knight Rider (original series) episode "Junkyard Dog" which sees KITT dumped in an acid pit and literally gutted alive (it's the only time we ever see the nigh-indestructible Knight Industries Two Thousand calling for help). The reactions of the team when he's hauled out, and KITT's resulting PTSD, are heartbreaking for fans; especially the reaction of Michael, who spends hours sitting around outside of the lab, like a nervous family member outside of an operating theatre, while the team is trying to repair him. And if the episode itself gets to you then for the love of god, don't read the script.
- KITT tends to do this to people a lot. And given that KITT is essentially a sentient car that's saying something. All we have to get attached to is his personality.
- Amoral Attorney Jeff Winger delivers a lecture on this in the Pilot of Community. Ironically, it's a subversion of Pet the Dog.
- In Star Trek: The Next Generation most of Data's interactions with his crew mates can be attributed to this. He's reasonably convincing as a sentient being and is probably one of the most sympathetic characters in the entire franchise, but he lacks emotions and empathic awareness and several characters have argued that he is effectively a highly complex walking computer which may or may not have a soul. Yet the crew encourages him to create and socialize, many consider him a friend, and treat him as if he were fully capable of feeling. They even encouraged him to form a romantic relationship even though this, technically, should be impossible. Actors from the show have stated that half Data's appeal comes from the empathy we feel towards him: we feel what Data cannot feel, and feel sorry because he can't.
Riker: For an android with no feeling he sure managed to evoke them in others.
- This is exactly what makes the episode with his daughter, Lal, such a Tear Jerker (double the empathy objects). He expresses regret (such as he is capable of feeling) that he cannot share in her feelings of love and she responds that she will try to feel it enough for both of them.
- In The Sims 3, If a Sim with the Unlucky or Loser trait dies of anything but old age, the Grim Reaper will revive them on the grounds that he "feels sorry" for them, and that they provide too much amusement to be killed off.
- Karst in Golden Sun: The Lost Age has a large fan following, and not just because of what she wears. Her relatively large amount of screen time and easily-relatable motivation make her the most sympathetic antagonist in the series, and one of the most well-developed and sympathetic characters in the series, as well (though, considering it is Golden Sun, that's not saying much).
- Pretty much the whole point of Warbot in Accounting is to make the audience feel pity for another literal killing machine. Unlike Cameron, however, this machine has no face, voice, appendages, ability to emote, and is basically a box with a giant camera lens coming out of the center. It works. Painfully well.
- Discussed in Sinfest, where Baby Blue objects to a story with a sympathetic protagonist; she gives Fuschia a physics textbook to read to the damned instead.
- One of the Æon Flux shorts viciously subverts this, showing a series of characters, each given screen time alone and characterization to make the audience connect with them, and each of whom becomes the subsequent Mook to be slaughtered by another character that the audience is being told to empathize with.
- Cracked.com introduces the monkeysphere, its name for what psychologists know as Dunbar's number. There is a finite number of simultaneous relationships that a human can maintain, with a small error-margin to account for certain personal differences. And to add insult to injury, fictional characters can count, too. So if you spend your time reading a lot of fiction and really getting to know the characters, you're cutting back the number of real people you can meaningfully get to know.
- A really grotesque version is seen in many ideological movements. A large part of the reason the Nazis got away with so much is that they were able to manipulate the world's otherwise laudable sympathy for the country that lost the last war.
- On a Lighter and Softer note (sort of) one Amish woman got a beer bottle thrown in her face by a passing driver. She was right away given plastic surgery from private contributions from people who did not know her.
- They do put him back together without killing him, but that's horrifying in an entirely different way.