EXT - THE WATER HOLE: As the dawn sky brightens, Moonwatcher and his tribe begin their day at a small water hole.

The Others soon arrive.

They are there on the other side every day.

That did not make it any less annoying.

There are several of them, and it is impossible to distinguish them from the members of Moonwatcher's own tribe.

As Moonwatcher's tribe sees them coming, the Others begin to angrily dance and shriek, and his own people reply in kind.

The confrontation lasts a few minutes - then the display dies out.

The Others earn territorial victory with their display of intimidation, Moonwatcher's tribe retreats. The Others triumphantly claim the right to fill their bellies with muddy water.

NIGHT TERRORS: Over the valley, a cold wind blows down from the distant mountains. It would be very cold tonight - but cold, like hunger, was not a matter for any real concern; it was merely part of the background of life.

Moonwatcher stirs when shrieks and screams echo from a distance, and he does not need to hear the occasional growl of the leopard to know what is happening. The leopard has taken down a zebra.

Moonwatcher and his tribe are nested in a shallow cave, which is little more than an indention of a rock formation. The leopard's cadence of growls have the tribe's undivided attention, no one is asleep.

Of all the creatures who had ever lived on Earth, Moonwatcher's race was the first to raise their eyes with interest to the Moon, and though he could not remember it, when he was young, Moonwatcher would reach out and try to touch its ghostly face.

EXT CAVE - NEW ROCK: Dozing fitfully, Moonwatcher is startled when he opens his eyes. He sits up and fear creeps slowly into his soul. Never in his life - already twice as long as most members of his species could expect - has he seen anything like this. His alarm turns into shrieks, the rest of the tribe begins to stir.

Moonwatcher is face to face with the New Rock, a cube about fifteen feet on a side, and it is made of a material unknown to him. There are no natural objects to which Moonwatcher can compare this apparition. The tribe scramble out of the shallow cave and away from the New Rock. They explode with primal tantrums not unlike their failed attempt to intimidate the Others at the water hole.

Though he is wisely cautious of most new things, Moonwatcher approaches the New Rock. He inches forward then back repeatedly, testing it for any aggression.

As nothing happens, Moonwatcher puts out his hand and touches it quickly with his finger tips, then retreats. He does this repeatedly till he gains confidence to touch the New Rock with his open palm, he feels a warm, hard surface.

The rest of the tribe eventually settle down as they see that no harm has come to their leader. They too approach the New Rock feeling its surface with great curiosity.

After several minutes of intense thought, Moonwatcher arrives at a brilliant explanation. It is a rock, of course, and it must have grown during the night. There are many plants that do this - white, pulpy things shaped like pebbles, that seem to shoot up in the hours of darkness. It is true that they are small and round, whereas this is large and square; but greater and later philosophers than Moonwatcher would be prepared to overlook equally striking exceptions to their laws.