“They are very young. And on their earth, as they call it, they never communicate with other planets. They revolve about all alone in space.""Oh," the thin beast said. "Aren't they lonely?”

“I closed my eyes and listened carefully for the descendants of Sputnik, even now circling the earth, gravity their only tie to the planet. Lonely metal souls in the unimpeded darkness of space, they meet, pass each other, and part, never to meet again. No words passing between them. No promises to keep.”

“SOLIDAO, LONELINESS.What is it that we call loneliness. It can't simply be the absence of others, you can be alone and not lonely, and you can be among people and yet be lonely. So what is it? ... it isn't only that others are there, that they fill up the space next to us. But even when they celebrate us or give advice in a friendly conversation, clever, sensitive advice: even then we can be lonely. So loneliness is not something simply connected with the presence of others or with what they do. Then what? What on earth?”

“A new consciousness is developing which sees the earth as a single organism and recognizes that an organism at war with itself is doomed. We are one planet. One of the great revelations of the age of space exploration is the image of the earth finite and lonely, somehow vulnerable, bearing the entire human species through the oceans of space and time.”

“Lingering is so very lonely when one lingers all alone.”

“The moon, our own, earthly moon is bitterly lonely, because it is alone in the sky, always alone, and there is no one to turn to, no one to turn to it. All it can do is ache across the weightless airy ice, across thousands of versts, toward those who are equally lonely on earth, and listen to the endless howling of dogs. (“A Story About The Most Important Thing”)”