Saylor.org's Comparative Politics/Social Science Theory and Reasoning

Realist theory
This is perhaps the oldest theory in the science of politics. Realist theory generally focuses on three elements:


 * 1) The state of world politics is a world of chaos (Hobbes) with a habitual competition for power (political) resources to control scarce natural resources.  The most important assets to avoiding a world of chaos are military and economic power and control.
 * 2) Life can be “nasty, brutish and short” unless people organize for the power to protect themselves to cope with chaos.
 * 3) States act as unitary, rational actors to maximize their own power resources & attempt to acquire greater security and economic wealth.

Structural-Realism or Neo-Realism
This empirical variant believes that structural factors dominate individual and internal/cultural differences. For example, policy creators may make the wrong or different decisions due to the need to make choices in a world of incomplete information; not due to individual or cultural value differences.

Classical-Realism
This empirical variant believes that the state needs true “statesmen” who understand power politics. The emphasis is that individual actors (decision-makers) can make a difference. Moreover, this variant also feels that if policy makers operate out of normative values (e.g. human rights, promotion of democracy) or respond to internal domestic pressures, it is a big mistake.

Hobbesian Realist
This theory assumes that the world is in constant chaos and is rare to find common interests. With emphasis on hard power (military or economic coercion or force), Hobbesian realists feel that compromise is a sign of weakness. This variant prefers unilateral action because of its disdain of the constraints multilateral institutions. Authoritarian rule is accepted because it is an exchange for civil order.

Machiavellian Realist: Political Theory in Medieval Practice
Machiavelli described and recommended a pragmatic approach to politics as it was in reality, rather than the noble and idealized approach that had previously been described. While this theory assumes the world is in constant chaos, they feel there is still a positive sum. Because this variant feels that compromises that serve everyone’s interest is possible, skilled diplomacy is just as important as military power. Machiavellian realists are concerned with the possibility of imperial-overstretch (involved with too many conflicts at once), so they always calculate utility of action. Machiavellian Realists are not opposed to multilateralism, however, they will go their own way if it serves their interests.

Realist theorists

 * Thucydides, Peloponesian War, 431-404 BC – Greek/Athenian.
 * Sun Tzu Art of War (China - 2,000 years ago - 1st century BC)
 * Niccolo Machiavelli, The Prince, Italian, 1500s Europe
 * Thomas Hobbes, Leviathon, English, 17th Century
 * Karl Von Clausewitz, On War, Prussian-German, 19th Century
 * Hans Morgenthau, Politics Among Nations, American 20th century
 * Henry Kissinger, Diplomacy, American 20th century
 * Kenneth Waltz, Theory of International Politics, American, 20th century
 * Paul Kennedy, Rise and Fall of Great Powers, American 20th Century.
 * Steven D. Krasner, Defending the National Interest, American, 20th Century.
 * John Mearsheimer, Tragedy of Great Power Politics, American, 20th Century
 * Chanakya, Arthashastra, 370-283 BC - Indian/Maurya.