Prior to the research done by Copernicus in the "revolutions of the heavenly spheres," the Earth was thought to be the center of the universe. The Sun, the planets, and all of the stars were thought to revolve around the Earth. Copernicus proved this to be untrue; however, his work was deemed heretical by the Catholic church and would take some time to be accepted outside of scientific circles.

Deism emerged for the first time in Europe during the Scientific Revolution. As scientists and thinkers began to understand more about the world, the mysticism of earlier periods began to fade and was replaced with growing comprehension and awareness. Deism is the belief that while God created the world, He did so with certain rules and laws that cannot be broken and now does not interfere in the lives of men or the existence of the world. This is called the belief in the "watchmaker" God.

The growth of Humanism, which emphasized the ability of human beings to think rationally and solve problems using the logic, evidence, and critical thought recovered from the ancient world, can be understood as a precursor to the Scientific Revolution. 

Isaac Newton is one of the most important figures of the Enlightenment and the Scientific Revolution. He discovered gravity and was, with Leibniz, the co-inventor of calculus. He also is credited with discovering the three laws of motion, which remain extremely important to our understanding of physics and the universe. 

Copernicus hid his findings for most of his life, only publishing them when he was close to death, for fear of retribution from the Catholic Church. Galileo likewise hid his research for some time before finally deciding to publish his work, because not doing so would be to go against his conscience. Both men feared retribution from the Catholic church. During the Scientific Revolution, all scientists who disproved a "fact" about human beings or the universe that could be found in the Bible faced scorn, punishment, and even execution at the hands of the Catholic Church, which was desperate to retain control over the understanding of the place of humans and God in the universe.

Isaac Newton did a great deal to advance human understanding, including inventing a whole system of mathematics that we call calculus. His most famous achievement, however, is his discovery of the law of gravity, which changed the way scientists understood the universe. A famous quotation about Newton comes from the brilliant English Renaissance man Alexander Pope: "Nature, and nature's laws, lay bathed in night. God said 'Let there be Newton!' And all was light."

Whilst John Locke believed in liberalism and constitutionalism and limiting the power of absolute monarchs, Hobbes argued that absolutism was the only way to protect society from slipping into an anarchistic state of nature in which crime and chaos would reign. 

Leviathan is a seminal work of the Enlightenment period that stood in contrast to the writings of John Locke, Rousseau, and others. In Leviathan, Thomas Hobbes presents his arguments in favor of absolutism as a means of preventing society from descending into catastrophic anarchy. Hobbes argued in support of the absolute power of government to control mankind's base nature.

Voltaire was a French philosopher during the Enlightenment era who advocated fiercely for the protection of freedom of speech. Freedom of speech, according to Voltaire, is the best and perhaps only way to guard against the tyranny of government.

Descartes is an Englightenment-era philosopher, scientist, and mathematician, and his work in all three fields continues to be hugely influential today. He is famous for his reductive inquiry into the nature of existence that led him to one simple truth: "I think, therefore I am." Essentially, by doubting his existence, he was proving his existence, for for there to be doubt there must be something to do the doubting.