Working definition. A possibility is an unrealised arrangement that can be examined for meaning, consequence, and the conditions of its becoming.
Inherited meaning
Philosophy separates what is possible from what is actual and what is necessary. Political imagination adds a crucial dimension: societies often treat inherited arrangements as inevitable until an alternative becomes visible enough to organise around.
Meaning in the imagination economy
Generative systems can produce endless variations, but variation is not yet possibility. A meaningful possibility discloses a different relationship, institution, practice, or way of living. It changes the present by revealing that what exists is not the only form reality can take.
What changes in practice
Give a possibility actors, constraints, costs, maintenance, and a first reversible step. Compare it with the default future already being produced. Keep it open enough to be co-authored, but concrete enough to disagree with.