Hundreds of people are crammed into a tiny room and the room is pulsating—not in a figurative, metaphorical sense, but literally. Bodies bounce against each other, arms and legs thrash out angularly, and heads bang in unison. The walls and the floor and the ceiling feel like they are moving, and they very well could be. There’s no way to tell. This isn’t a show where you sway politely or groove only slightly. This is a religious convocation and you’ve come to collide with all the other assembled true believers.

This is hardcore, born out of the ruins of what was left of punk rock in the 1980s and fueled by a hatred of what America had become under Reagan. A response to the era’s cultural conservatism and a rejection of the glitz and decadence offered by rock music, it was, as Minor Threat front-man Ian MacKaye once said, “the manifestation of youth” in a time that worshipped tradition. The Gipper claimed “it’s morning in America” and hardcore answered: “IT’S FUCKING MIDNIGHT, MAN.”

Since the 80s, the story of hardcore has gained new chapters—post-hardcore, metal-core, deathcore, and a whole host of other “cores” that claim hardcore punk as their heritage. I can’t offer an authoritative account of what hardcore is, what it means, or how it came to be. But I can offer this: the emotional, spiritual, and physical topography of a hardcore show.

Here, it doesn’t matter which band or song is playing. The cultural critic and historian Greil Marcus once said that rock & roll could be born for the first time, anytime; the same is true for hardcore. In any hardcore song from anytime since this loud and abrasive form of human communication appeared on Earth, you can find the constitutive elements of hardcore. But let’s say that at this moment, the band playing is Bane, a straight-edge outfit from Massachusetts, and the song is “Ali v. Frazier I,” from the album called “Give Blood.”

When the first three chords ring out and the drums rumble to life, the match is struck. When singer Aaron Bedard begins to yell, the fuse is lit and you are the dynamite at its end. “How many more days will you sit / and talk about your ambitions / all that you can be / all that you are dying to be.” Once the beat gets going it cannot be stopped until the fuse is all burnt up. This song is about the connection between aspirations and mortality, and Bedard speeds through the lyrics like a driven man speeds through life towards death. The guitars and bass gallop through bars of power chords and continue to chug as the snare hits relentlessly.

Ending the last verse, Bedard screams, “if not you, if not this…/what else is there but death.” Now, the fuse is gone. The light goes out. The chords fade. The song falls into a kind of slow motion, thrusting the listener into the nearly halted milliseconds at the moment before combustion. First there is a sense of suspension, as though the song has just taken a breath. And then the drums come back to life. The words tear out of Bedard’s throat, “it’s all on you!” Everything explodes.

In an instant, you become just one more molecule bouncing violently against all the others in the mosh pit, hundreds of little explosions continuing to burn. There is always the kid with the bloody nose, grasping through the crowd just to touch the stage that his favorite band is standing on. The blood streams down his face, the result of an errant fist in the pit. It might be broken, but he doesn’t care, because his chest is vibrating in the frequency of the band’s down-tuned guitars and his heart is beating with every snare.

The mosh pit is about violence—an outlet for rage against the authoritarian confines of everyday life and disgust for a society that is corrupt to its very core—but it also isn’t about violence. For all the bodies crashing and heads crunching and arms flailing, this isn’t war: this is religion. This is self-flagellation in pursuit of an altered state that cannot be induced by any substance other than the collective will of people in that tiny room to ram into each other with all their strength.

Human beings have done things like this for centuries, like the monks who whip themselves or lie on beds of nails to reach a higher spiritual plane. The mosh pit is just another ritual of transcendence. For every moment that you thrash against the other people in the swirling mass of elbows and fists, you forget that time has passed. You are so much in the moment that time as an eternal sequence of passing moments grinds to a halt.

There is a certain paradox to the mosh pit, that in this moment of intense physicality you lose a sense of your own body. Limbs, people, and faces slam into you and you barely feel it. In Old Norse literature, the berserkers were elite warriors who would work themselves into such a state that they demonstrated superhuman strength and courage. Fighting through the arms and legs of a hundred skinny suburban kids is pretty far from facing down Christian conquerors to protect the pagan homeland, but its probably the closest thing  those kids will ever get to fighting for something they believe in.

Those unfamiliar with the mosh pit might view it cynically, as an excuse for gratuitous violence carried out by cruel and angry people. And there are, without a doubt, a few people who come to the pit looking to start a fight. But the mosh pit is governed by a kind of camaraderie, an ethical code or unspoken rule that states its purpose is to turn music into something collective, physical, and participatory; not to beat the shit out of each other. I’ve seen people help each other up when they fall in the pit or apologize for hurting someone more times than I’ve seen fist fights.

Hardcore has always been a form of protest—against everything and anything from bourgeois family values to rapacious capitalism. Its call for revolution, for “no more control, no more rules,” is an effusion of indignation mixed with responsibility and solidarity that appears in few other genres. That call is now forty years old, but it continues to ring out today.

In the song “The New Fury” by Verse, a band from Providence, Rhode Island, front-man Sean Murphy screams of “devastation soon becoming fuel for the masses new fury.” The song is an example of Marcus’ maxim about the “anytime-ness” of rock & roll and hardcore. In it, Murphy condemns the present and predicts the future. But “The New Fury” was released in 2008 and that future is the present. Chillingly, the words “we still struggle with the fact that one percent has ninety-nine on their knees” appear in this song, written four years before Occupy Wall Street discovered them and turned them into a slogan.

Hardcore is most often an expression of anger, which is why it is more necessary today than ever. It is impossible to continue on contentedly when eighteen year old kids are being murdered in broad daylight by cops who walk free, when everywhere people are suffering at the hands of arbitrary power, and when there is nothing you can do about it.

But hardcore isn’t just anger. It can even be playful, like Choking Victim’s “Hate Yer State,” which begins with completely incomprehensible but consciously and hilariously garbled spoken word. Hardcore is what its name is meant to evoke. It is intensity and fervor. It is sweat, blood, and tears, all at the same time. It is everything that you cannot find in a Top 40 set or in the mumble-core doldrums of bands like Mumford and Sons.

That intensity, or more accurately the lack of it, is why the thousands of bands that cropped up in the early 2000s, clawing their way out of the gloomy shopping-mall sprawl of New Jersey and Boston, trying to merge catchy chorus hooks with heavy breakdowns will be forgotten, while no one will ever forget Minor Threat. This isn’t merely a matter of chronology, that without the latter the former could not exist. Instead, it’s a matter of spirit—the kind of spirit that turned Ian MacKaye’s voice into an indelible mark bleeding through successive generations.

Hardcore’s spirit, its intensity, is nearly impossible to locate in contemporary music. This is because so much of music today seems to operate within a limited range of emotions. Where there is anger, it is often cloaked with irony. Where there is pain, it is usually pain that is numbed. Where there is sadness, it is typically melancholy but almost never despair. What is missing is the visceral—the kind of anger that can only be expressed in a throat- shredding scream, the kind of pain that gives way to rage, the kind of sadness that demands self-obliteration instead of self-regulation. This is what is absent from trip-hop’s catatonic, perpetual chillness, from indie-rock’s irritating eagerness, and from EDM’s molly-gnashing mindlessness. Each of those genres has a time and a place, a moment when what they offer is what you need. But to live in a world where the only available emotions are the ones they offer is to live in a world without sharp edges. And a musical balm like that can be satisfying for song long. When it wears off, the demand for something more grows.

At the end of the show, the last chord fades. The lights turn on. You are drenched in a full- body baptism of your own perspiration. You are hoarse from screaming along, from hoping that one more push from your vocal chords could make that one last song last forever. You are sore from the hours of jostling and ramming into the people around you. You are exhausted. But in a way, you are also reborn.

In basements across America, thousands of devotees to the faith will try to recreate that moment, to enter into the realm of the extraordinary as an escape from the crushing ordinariness of their lives. During the day, they are grocery store clerks and Wal-Mart associates, Genius Bar workers and college students. But at night, the pit makes them holy warriors, chieftains of a domain with a population of one. They long for the next moment of catharsis. They wait impatiently to feel that power and energy again.