The Three-Body Problem

Cixin Liu's The Three-Body Problem begins during the Chinese Cultural Revolution with a secret military project that sends signals into space to make contact with aliens.

An alien civilization on the brink of destruction manages to capture the signal and sends its fleet to invade Earth.

Meanwhile, on Earth, humanity has conflicting ideas about the fate of the planet. Some factions want to welcome the aliens and help them conquer a world seen as corrupt, while others want to fight against the invasion.

Favorite quotes from the book:

In the shooter hypothesis, a good marksman shoots at a target, creating a hole every ten centimeters. Now suppose the surface of the target is inhabited by intelligent, two-dimensional creatures. Their scientists, after observing the universe, discover a great law: "There exists a hole in the universe every ten centimeters." They have mistaken the result of the marksman's momentary whim for an unalterable law of the universe.

The farmer hypothesis, on the other hand, has the flavor of a horror story: Every morning on a turkey farm, the farmer comes to feed the turkeys. A scientist turkey, having observed this pattern to hold without change for almost a year, makes the following discovery: "Every morning at eleven, food arrives." On the morning of Thanksgiving, the scientist announces this law to the other turkeys. But that morning at eleven, food doesn't arrive; instead, the farmer comes and kills the entire flock.

By the time you're my age, you'll realize that everything you once thought mattered so much turns out to mean very little.

These are the rules of the game of civilization: The first priority is to guarantee the existence of the human race and their comfortable life. Everything else is secondary.

On Earth, humankind can step onto another continent, and without a thought, destroy the kindred civilizations found there through warfare and disease. But when they gaze up at the stars, they turn sentimental and believe that if extraterrestrial intelligences exist, they must be civilizations bound by universal, noble, moral constraints, as if cherishing and loving different forms of life are parts of a self-evident universal code of conduct.