The Prince is widely thought to be one of the first works of modern political philosophy. Machiavelli was the first to decisively divorce politics from ethics. His political realism influenced many important figures in the developing field of materialist philosophy, including Francis Bacon, John Milton, Spinoza, Rousseau, Hume, Edward Gibbon, and Adam Smith. His treatise had a profound impact on political leaders throughout the modern west, including the founding fathers of the United States who, like Machiavelli, favored a republican form of government. Machiavelli emphasized the need for looking at the "effective truth" based on experience and historical fact, rather than theorizing about ideal republics or imaginary utopias. Controversial for advancing an amoral view of the world where any means are justified if they serve the ambitions of power, The Prince also ironically seems to undermine its own doctrine by predicting in some ways the doom of a strictly realist approach.