The Relations of Possibility: IV. The Possible Is Not the Imagined

We can imagine almost anything.

A mountain can fly. A stone can speak. Tomorrow can contain an event that has never occurred before.

But imagination is not possibility.

The distinction matters because we often use possible to mean little more than conceivable.

If we can imagine something without contradiction, we are tempted to call it possible.

But the world is less permissive than imagination.

A stone may be imagined floating in the air. Yet whether it can actually do so depends upon the relations in which the stone participates: its mass, its surroundings, the forces acting upon it, and the structure of the physical world.

Possibility is therefore not simply a property of an idea.

It is a property of a situation.

More precisely, it is a property of what the relations constituting that situation leave open.

This changes how we should think about possibility.

The possible is not an invisible collection of events waiting somewhere in the future. Nor is it a catalogue of everything that can be described without contradiction.

It is what the present permits to become actual.

A door makes passage possible because of its relation to the spaces on either side, the opening itself, and the things that might pass through it.

A road makes some journeys possible because of its relation to the landscape.

A physical system makes some future states possible and excludes others because of the relations that constitute its present state.

Possibility therefore has a history.

Change the relations, and the possibilities change with them.

This is why the future cannot be understood simply as an unknown region containing everything that might happen.

The future is constrained by the present.

But it is not determined in the sense that only one outcome must necessarily occur.

There may be several futures that remain open.

What matters is that they are not arbitrary.

They arise from the structure of what exists now.

We can now see the significance of the distinction.

Imagination asks:

What can I conceive?

Possibility asks:

What can this situation become?

The first belongs to the space of thought.

The second belongs to the relations of the world.

And the two can diverge dramatically.

A black hole makes the distinction especially clear. We can imagine an object escaping from inside the event horizon. But the causal structure of the geometry does not leave that future open.

The imagined future remains conceivable.

The physical future does not.

So possibility is neither everything we can imagine nor everything we can describe.

It is what relational structure leaves open.

And now the question becomes more precise.

If the possible is what the present leaves open, then perhaps a future is not something waiting ahead of us at all.

Perhaps a future is a relation to what has not yet happened.