Fields of Life: Seven Ways the One Meets the Many: 7 Slime Moulds: Individuation That Comes and Goes

Phase transitions in the many–one relation

Slime moulds sit precisely at the fault-line where our inherited metaphysics collapses under its own assumptions. They refuse the default commitments we smuggle in whenever we say “organism,” “group,” “individual,” or “colony.” Instead, they enact a shifting, phase-dependent field of individuation whose coherence cannot be localised in any particular element. A slime mould is neither one nor many; it is the relational drift between them.

To watch Dictyostelium or Physarum is to witness a system whose potentials reorganise depending on the perspective enacted. What looks like a population of autonomous cells in one phase becomes—through nothing more than altered gradients and collective construals—a single motile body with distributed cognition. The possible is not a reservoir in the background; it is the live field that the collective continuously carves and re-carves as it shifts between modes.

The signal as an invitation, not a command

The canonical story of cyclic AMP as the “attractant” that draws isolated amoebae together misdescribes the phenomenon. Nothing commands; nothing obeys. Instead, each cell construes the chemical field as an inclination—a structured readiness that can be actualised as coordinated movement. The signal does not transmit information about something; it positions each cell into a perspective where certain motions become imminent.

Through these construals, a phase transition is initiated: the population ceases to enact itself as a swarm of loosely associated cells and begins to enact a migrating pseudoplasmodium. The “slug” is not an entity that emerges from many; it is a perspectival reorganisation of the collective’s potential. One moment the system displays high-resolution individuation; the next, individuation practically disappears into a single flowing body.

Collective cognition without stable selves

When slime moulds navigate mazes, optimise routes, or select the most nutrient-rich path, we are tempted to ask where the “decision” is made. But this question presupposes a stable agent. Slime moulds undo that temptation by distributing construal across the dynamic pattern of contraction waves, chemical flows, and local adjustments in cytoplasmic streaming.

Here, cognition is not a property of an individual but a temporary mode of coherence enacted by the colony-as-one. The “self” that solves the maze is not the “selves” that foraged separately hours earlier. Identity is not a thing the slime mould has; it is a region of its readiness field—a perspective enacted when certain gradients dominate.

Becoming-one and becoming-many as complementary potentials

Slime mould life cycles expose individuation as a cline, not a category. The shift from many to one is not a merger of units; it is the collective’s reorientation toward a new configuration of possibility. Likewise, the shift back—from slug to fruiting body to dispersing spores—is not fragmentation but a perspectival redistribution of potential across different scales.

This fluidity forces a deeper revision of “organism”: not as an entity that maintains identity through change, but as a pattern of constraints that can tighten or loosen depending on what the system construes as viable. The slime mould’s gift is the demonstration that stability is optional, and that identity itself can be episodic.

A temporary whole that knows how to dissolve

The elegance of slime mould individuation lies in its refusal to essentialise its own wholeness. Wholeness is simply one position in its landscape of readiness—a phase where synchrony, flow, and collective contraction actualise a world that can only be enacted by acting as one. But when the ecological or developmental gradient shifts, the colony releases this perspective. The whole dissolves, not into chaos, but into a renewed multiplicity of potential vantage-points.

In slime moulds we find a living argument for individuation as perspectival stratification: a system whose ontology is not defined by being one or many, but by its capacity to move between them. They instantiate a truth often denied in biological discourse: that identity can be a transient achievement rather than a substrate.

Slime moulds do not merely model phase transitions; they live them. And in doing so, they remind us that selfhood is a mode of coordination—one that can be entered, exited, recombined, and re-enacted as the world requires.