Shadows of Forgotten Ancestors, by Ann Druyan and Carl Sagan (1992)

Events of remote ages, long before humans came to be, are critical, we concluded, for an understanding of the trap that our species seems to be setting for itself.

"Who are we? The answer to this question is not only one of the tasks, but the task of science." — Erwin Schrödinger

Are we capable, if need be, of fundamental change, or do the dead hands of forgotten ancestors impel us in some direction, indiscriminately for good or ill, and beyond our control?

"God is an invention of Man. So the nature of God is only a shallow mystery. The deep mystery is the nature of Man." — Nanrei Kobori, late Abbot of the Temple of the Shining Dragon

We ourselves, the writers of this book, have so short a reach into our family histories that we can peer clearly only two generations back, dimly three, and almost not at all beyond that. We do not know even the names—much less the occupations, countries of origin, or personal histories—of our great-great-grandparents. Most people on Earth, we think, are similarly isolated in time.

We are cut off from our past, separated from our origins, not through some amnesia or lobotomy, but because of the brevity of our lives and the immense, unfathomed vistas of time that separate us from our coming to be.

As the infant is said to feel it is the center of its Universe, so we were once sure, not just of our central position, but that the Universe was made for us. This old, comfortable conceit, this safe view of the world has been crumbling for five centuries. The more we understood of how the world is put together, the less we needed to invoke a God or gods, and the more remote in time and causality any divine intervention had to be. The cost of coming of age is giving up the security blanket. Adolescence is a roller coaster ride.

We have not met our forgotten ancestors, but we begin to sense their presence in the dark. We recognize their shadows here and there. They were once as real as we are. We would not be here if not for them. Our natures and theirs are indissolubly linked despite the aeons that may separate us. The key to who we are is waiting in those shadows.

An immense mass of gas and dust is swiftly collapsing under its own weight, spinning ever faster, transforming itself from a turbulent, chaotic cloud into what seems to be a distinct, orderly, thin disk. Its exact center smolders a dull, cherry red. Watch from on high, above the disk, for a hundred million years and you will see the central mass grow whiter and more brilliant, until, after a couple of abortive and incomplete attempts, it bursts into radiance, a sustained thermonuclear fire. The Sun is born. Faithfully, it will shine over the next five billion years—when the matter in the disk will have evolved into beings able to reconstruct the circumstances of its origin, and theirs.

A dense clump of material attracts adjacent gas and dust, grows larger and more massive, more efficiently draws matter to it, and is off on its way to stardom. When the temperatures and pressures in its interior become high enough, hydrogen atoms—the most abundant material in the Universe by far—rare jammed together and thermonuclear reactions are initiated. When it happens on a large enough scale, the star turns on and the nearby darkness is dispelled. Matter is turned into light.