Niccolò Machiavelli (3 May 1469 - 21 June 1527) was an Italian Renaissance diplomat, philosopher, and writer, best known for The Prince, written in 1513. He has often been called the father of modern political philosophy or political science. For many years he served as a senior official in the Florentine Republic with responsibilities in diplomatic and military affairs. He wrote comedies, carnival songs, and poetry, and worked as secretary to the Second Chancery of the Republic of Florence from 1498 to 1512, when the Medici were out of power.
Machiavelli considered political battles, not through a lens of morality, but as though they are a board game with established rules. His experience showed him that politics has always been played with deception, treachery and crime. He also notably said that a ruler who is establishing a kingdom or a republic, and is criticized for his deeds, including violence, should be excused when the intention and the result is beneficial.
Carl von Clausewitz (1780 - 1831) was a Prussian general and military theorist who stressed the "moral" (in modern terms, psychological) and political aspects of war. His most notable work, Vom Kriege (On War), was unfinished at his death. Clausewitz was a realist and, while in some respects a romantic, also drew heavily on the rationalist ideas of the European Enlightenment. He stressed the dialectical interaction of diverse factors, noting how unexpected developments unfolding under the "fog of war" (i.e., in the face of incomplete, dubious, and often completely erroneous information and high levels of fear, doubt, and excitement) call for rapid decisions by alert commanders. He saw history as a vital check on erudite abstractions that did not accord with experience. He argued that war could not be quantified or reduced to map-work, geometry, and graphs. Clausewitz had many aphorisms, of which the most famous is "War is the continuation of politics by other means."
