Thousands of years ago, a man with his small tribal group, had managed to hunt a deer, when they saw among the branches that a strange thing was moving; they were not bears, or reindeer or deer, they were animals that walked on two legs and carried clubs. They were other human beings and could be dangerous.
The group that had just hunted, raised their arrows and shouted to warn visitors, they also growled, but at the gesture of their boss, abandoned their weapons and raised their hands to show that they were empty. After a moment of silence, both bosses began to make friendly grunts, to reassure each other mutually.
In the end, those bipedal animals exchanged axes and other elements, and ended up sharing the hunt of that day.
That happened in the mists of time and for centuries and millennia, humans sometimes used their weapons, and in others they held hands. It has been the same story since then.
And the highest encounter between two humans as a reminder of that afternoon at the foot of a cave, occurred beyond the clouds and our eyes, but very close to our joys and hopes. The one was American and the other Soviet, and they were not next to any cavern, but weightless, flying in outer space at 40,000 kilometers per hour. One commanded the American ship Apollo, the other, the Soviet Soyuz.