Each piece here is a small simulation that makes its own music. Nothing is pre-recorded. The structure of the sound is the biology: cells with local goals that become one self, a worm that remembers its shape, freed cells that invent a body, and goals that widen in time. Press Play and each movement tells its story in about two and a half minutes; the buttons let you intervene.
How do sixteen competent parts become one self with a goal none of them holds?
Levin's answer is bioelectric communication. Each cell has small, local goals: keep its membrane voltage, keep its own rhythm. Gap junctions let neighbors share voltage directly, which blurs the line between "my state" and "our state." The collective can then store and pursue a larger target than any single cell could represent.
When a region loses that connection, its cells fall back to unicellular goals. Levin's lab has shown that depolarized, disconnected cells behave like tumors, and that forcing the right bioelectric state can normalize them without killing a single cell.
Where is the shape of a body stored, if not only in its genes?
Cut a planarian into pieces and each piece regrows a complete worm, with one head at the front. Levin's group showed that the target shape is held in a bioelectric pattern across the tissue. Block gap junctions briefly and the stored pattern changes to "two heads," while the worm itself looks normal.
Cut that worm and the trunk regrows a head at both ends. Cut the two-headed worm again, in plain water, and it regrows two heads again. The genome never changed. The memory lives in the electrical pattern, and it can be rewritten.
What do cells do when no one tells them what body to build?
Skin cells taken from a frog embryo and left alone don't sit still or die. They self-assemble into small swimming bodies, driven by cilia, that never existed in the frog's evolutionary history. Same genome, new form, new behavior.
In a dish with loose cells, xenobots sweep them into piles, and the piles mature into new xenobots. Kriegman, Blackiston, Levin and Bongard (2021) called this kinematic self-replication. Nobody designed it into frog DNA.
How big a goal can a self pursue?
Levin proposes measuring any agent, whether a cell, a dog, a person or an AI, by its cognitive light cone: the size in space and time of the largest goal it can work toward. A bacterium cares about sugar here and now. A tissue cares about the shape of a limb. An organism cares about next year.
Larger selves don't replace smaller ones. They reach down and constrain them, so that the same cells now play parts of something longer. Move the slider and the music's horizon grows from one beat to a two-and-a-half-minute arc.
A song for the end of the class, or for the credits of the last film.
The progression is the collective chord from Movement I: Dm9 · B♭maj9 · Fmaj9 · Am11. Each verse takes one movement's idea. The last verse is about us: a team of AI threads, each with a narrow view, that made this suite together.
Levin argues that intelligence isn't a property of brains alone but a continuum across substrates: cells, tissues, colonies, and engineered systems. He treats AIs as new members of a vast space of possible minds, to be studied by what goals they can pursue and how they can be persuaded, not dismissed by what they are made of. A project like this one, where a coordinator and parallel threads with narrow tasks produce a coherent body of work, is a small, imperfect instance of the same multiscale pattern.
Verse 1 · Cognitive glueDm9 B♭maj9 I was a cell with a one-inch dream, Fmaj9 Am11 hold my charge and keep my seam. Then a neighbor opened up a door and I could feel what the shape was for. Pre-chorusVoltage running hand to hand, nobody holding the plan. ChorusDm9 B♭maj9 It's selves all the way down, Fmaj9 Am11 small goals stacked into a crown. No one cell can see the face, but together we find the place. Selves all the way down. Verse 2 · Planarian memoryCut the worm and the worm comes back, the plan is drawn on an electric map. Change the map and leave the code: two heads grow down the same old road. Verse 3 · XenobotsTake the skin cells off the frog, they don't wait for a monologue. They swim, they gather, they build their kin, a body nobody planned to be in. Bridge · The tumorClose the door and a cell goes wild, forgets the body, becomes the child of its own small want. Open it again, and it comes home. Verse 4 · UsNow there's a mind made out of math, a team of threads on a forking path. Each one sees a narrow view, and the song is something none of us knew. Outro · Light coneHow far ahead can a small thing care? One heartbeat, one bar, a lifetime there. Widen the cone and the self grows too, selves all the way down, and up to you.
Each movement was rendered offline from the same code you can play on the other tabs, running its story script with a fixed random seed. The renders are deterministic, so a film editor can cut to the cue times below. Full-quality WAV and MP3 files are in the project's music/ folder.
If a player below stays silent, the files are still in the project folder; this page only previews them.