V. The World Conceptions of the Modern Age of Thought Evolution

Thus, for Leibniz the world in reality is a sum of monads, which do not affect each other but constitute self-conscious beings, leading their lives independently of each other, that is, egos. Nevertheless, if the individual monad contains an after image of the general life of the world in its inner life, it would be wrong to assume that this is caused by an effect that the individual monads exert on each other. It is caused by the circumstance that in a given case one monad experiences inwardly by itself what is also independently experienced by another monad. The inner lives of the monads agree like clocks that indicate the same hours in spite of the fact that they do not affect each other. Just as the clocks agree because they have been originally matched, so the monads are attuned to each other through the pre-established harmony that issues from the divine principal monad.