Where new things come from
Not all possibilities exist at once. At any moment, only those configurations one step from the actual are reachable. Stuart Kauffman called this the adjacent possible — the set of things that could come into existence given what already exists, but only those things. A room has doors, but behind each door are new rooms with new doors that were previously invisible. The space of possibilities grows as you explore it.
But what opens the doors? The mechanism, as Terrence Deacon clarifies, runs through three steps. First, redundancy: a working component gets duplicated, and because there are now two copies, one is freed from its current obligation. Second, degradation: freed from selection pressure, the spare copy drifts under entropy, accumulating neutral variations. Third, novel encounter: the degraded variant finds itself in a context it was never designed for, and something unprecedented clicks into place. The new function was not latent in the original. It was constituted by the encounter.
The key insight is that you cannot predict what will emerge. The adjacent possible is not a pre-computed list waiting to be discovered. It is constituted in real time by the collision of variants with contexts. This is why evolution is genuinely creative and not merely a search algorithm optimizing over a fixed fitness landscape. The landscape itself changes with every step taken upon it.
Biology knows this pattern intimately. Gene duplication creates redundant copies. Neutral drift differentiates them. Then one day a duplicated gene — freed from its ancestral role, reshaped by entropic wandering — encounters a novel molecular context and folds into a protein with a function that never existed before. The adjacent possible expanded, not because someone computed it, but because the right accident met the right context. This is where new things come from.