Leibniz combined physics, biology, introspec- tion, and theology into a worldview that was both strange and complex. One of Leibniz’s goals was to reconcile the many new, dramatic scientific discov- eries with a traditional belief in God. As we have seen, Spinoza attempted to do much the same thing by equating God and nature, thus eliminating any friction between religion and science. Leibniz’s pro- posed solution to the problem was … different.
With the aid of the newly invented microscope, Leibniz could see that life exists everywhere, even where the naked eye cannot perceive it. He believed that the division of things into living or nonliving was absurd. Instead, he concluded that everything was living. The universe consisted of an infinite number of life units called monads. A monad (from the Greek monas, meaning “single”) is like a living atom, and all monads are active and conscious. There is a hierarchy in nature, however, similar to the scala naturae Aristotle proposed. Although all monads are active and conscious, they vary in the clarity and distinctiveness of the thoughts they are capable of having. In other words, monads differ in intelligence. What is sometimes called inert matter is made up of monads incapable of all but extremely muddled thoughts. Then, on a scale of gradually increasing intelligence, come plants, microbes, insects, animals, humans, and God. Differences among all things in the universe, then, are quantitative, not qualitative. All monads seek to clarify their thoughts, insofar as they are capable, because clear thinking causes pleasure. Here is an important point of agreement between Aristotle and Leibniz, because Leibniz viewed a monad as a potential seeking to become actualized. In other words, each monad, and there- fore all of nature, was characterized by a final cause or purpose.