Religions have long explained the world as the creation of gods. Science proposes instead that the universe unfolds under a set of strict laws. In 300 BCE, Aristarchus studied eclipses and reasoned that they’re caused by the moon passing in front of the sun or Earth passing in front of the moon. From this, he deduced that Earth orbits the sun and that the stars are other suns. Science has since refined these theories to clarify that the universe, God-created or not, runs without the intervention of a supreme being.

Most people think of God as a personal being with whom one can have a relationship. Hawking defines God differently: “[K]nowing the mind of God is knowing the laws of nature” (28). God may have ordained those laws, but the rest happens of its own accord.

The universe contains three ingredients: matter, energy, and space. Einstein discovered that two ingredients, matter and energy, are actually both forms of energy. That energy, plus space, appeared suddenly in a “Big Bang,” out of nothing. This was possible because the energy involved was balanced by space, which contains negative energy. It’s like building a hill on a flat piece of land by digging a hole in that land to acquire the dirt to make the hill: “The positive side of things—the mass and energy we see today—is like the hill.