The Light: A Fictional History of Intelligent Thought

The year was.. Well, nobody had felt like inventing the number system of late, so it was some time in the pre-historic ages. A group of unassuming cavemen (assuming that they were indeed unassuming, which is quite a stretch if one thinks about it long enough) were sitting around in a cave, which was, basically, their daily activity. That's why there's no recorded history in the pre-historic ages. There was nothing going on. The cavemen were starting a conversation.
"Unk." said one caveman.
"Uh," said another.
"Unk-a-lunk!" exclaimed a third. The fourth caveman said nothing. The first caveman said, or would have said, assuming that languages had come into existence yet,
"Why Og, is something the matter?"
"No, Ump, I am fine." Og stared meaningfully out into the space in front of him.
"Og," said the second caveman, Thuh "What are you doing?"
"I'm contemplating my relatively puny existence in comparison with the vastly huge galaxy in which we live," he replied.
"Huh?" asked Thwack, the third caveman. This also conveyed the thoughts of Thuh and Ump.

"I'm having intelligent thought," explained Og. There was a moment of silence as the other three cavemen thought about what this might mean. The silence was followed by raucous laughter.
"Intelligent thought?" howled Ump.
"There's no such thing!" chortled Thwack.
"Really, Og," said Thuh, trying to catch his breath as he spoke, "You are a riot!" By this time, Og had had enough. He got to his feet and shouted,
"Now look here! Do you think that, perhaps, there might be other things besides our tribe, the caves, and the mammoths? Those crystal things in the sky at night, how many of them are there? Have you ever thought, just once, that we might not be alone?" The cavemen considered this for a bit. They scratched their thick, dirty, caveman heads, and tried to think about what it was that Og had said. Finally, Thwack said,
"Nope!" put in Thuh.
"Definitely not," Ump finally added. Og said,
"Oh, all right then," and sat back down.
"Uh," said Thwack.
"Unk," said Thuh.
"Unk-uh," said Ump.
"Unk-uh-lunk," finished Og.

Unbeknownst to the cavemen, Og's contemplation was the world's first intelligent thought. But it was not the last. Nor would it be for centuries to come. Actually, I believe that the last thought on earth was really,
"Whatever happened to that lovely wensleydale cheese log that cousin Colin sent me for Christmas." That itself is not exactly an intelligent thought, though it is a legitimate thought. But I'm getting ahead of myself. The real story starts thousands of years after Og's historical first epiphany.