Debates had been between different approaches in the development process of discipline of international relations. These are named ‘Big Debates’, and history of discipline are written with regards to these debates that are continuing different forms nowadays, and new debates will add in addition these. Basis debates make departure ‘four steps’ normatively in the development process of discipline of international relations. These are realism-idealism, behaviouralism-traditionalism, neorealism-neoliberalism (debate between paradigms) and Rationalism/positivism-critical/post-positivism debates.

              Idealism -Realism debate: it is the first debate the discipline of International Relations that had continued until today. Even if the debate is seen like old debate, it had shown up with different names and concepts repeatedly. Idealism provided to appear discipline of international relations with belief of positivism, wisdom and science as heritage of the age of enlightenment. When thesis of idealists about protecting peace is refuted with Versailles order, confidence in the idealism started to decrease. Realism claims that, scientific understanding of idealism is not systematic, is more value-laden, and they uphold that the world must be examined according to how it already is, not according to how it must. E.H Carr is one of the most important thinkers of Realism, and according to him, realism could get a scientific quality thereby assent of facts and to examine reasons and results of them. He had tendered an alternative like magic against the science that was idealism. Carr claims that idealism had shown up as a reaction against regulations between two wars, and became a trend approach. Hedley Bull, Martin Wight and Theodor Herzl have studies about realism. On the other hand, Winston Churchill and George F. Kennan defended realism with their politics and implementation, but until Waltz’s neorealism, realists do not have enough effort for to show up scientific understanding exactly. Hans Morgenthau believed science, but he defined shaped objective statutes as depending state of nature, and also he did not ever accept to be science international relations like natural science. Morgenthau had laid the foundations of classical-realism with his extensive searches. 1929 Economic Depression and Second World War refuted thoughts of idealists a vast scale. Winner of debate between realism and idealism cannot say realism because after that, by liberalism, neoliberalism and constructivism had made strong criticisms against realism. Idealism is important to provide confidence between states and for international law. Preventing the wars and became peace perpetual is the most important factor of idealism. Realism handles with state entirely. Idealism considers factors within state against realism. There are some debates in this term out of debate of realism and idealism. On the other hand, studies of academic international relations had generally been liberal (backstage of realism), some thinkers of realism had believed an intimate liberalism especially about domestic policy.

              Behaviouralism-Traditionalism debate: it is the second debate of international relations discipline, and it had shown up 1960s. There is no common opinion about when to start. It is seen as debate of being scientific, and not theoretical debate, on the contrary, is defined methodological debate. Data collection had created major differences between behaviouralism and traditionalism. The purpose of behaviouralism is to analyze international relation with natural science, and also they try to show to be an ology to international relations. David Easton(thinker of behaviouralism) expressed that, behaviouralism is the next stage to improve mankind. On the other hand, David Singer and Morton Kaplan(other thinkers of behaviouralism) had studied to determine tidiness and to find general statute with statistical data for international relations, and to develop scientific research methods for discipline of international relations. Hedley Bull and same thinking other thinkers claims that, judgement of cognitive and interpretational is the more important systematical collecting data, and they emphasized sophistication of world politics and unique nature of historical environment, but though traditionalists criticize behaviouralists, an alternative way is not tendered against behaviouralism. At the same period, there was Vasquez’s thesis, and according to him, even though they are saying different things, indeed, behaviouralists adopted a paradigm of realism, and, there are not essentially; just procedural differences between these approaches. Debate between behaviouralism-traditionalism had turned around realism, and also the debate had caused to show up positivism. Indeed we can say that behaviouralism had accepted four basic assumptions of positivism tacitly. Historical and scientific explanations had differed each other at this debate. It reflected regression to do between ‘ınternational relations is historical ,but it should not be scientific.’ obvious events ‘ involving generalities part of different time with historical environment .’ nowadays, historical and scientific explanations are not against each other, but discussion of history and science is still center of international relations, and every approach against positivism have to face with this subject.

              Neorealism-Neoliberalism debate: it is named debate between paradigms in International Relations. The debate had started to show up together with Thomas Kuhn in 1970s. Kuhn said that, scientific knowledge like positivists’ thoughts does not proceed by means linear, it will experience a crisis , and it will reconstruct ,and then it will continue, so a new paradigm will take over old paradigm in scientific revolutions exactly or partially. According to Kuhn, It was impossible to criticize a paradigm to another paradigm because followers of every paradigm were living different worlds. Domination of realism was continuing in 1970s until reformulate on its own. Neoliberalists like Joseph Nye and Robert Keohane criticize classical realists like E.H Carr and Hans Morgenthau about multilateral dependency and multi actor order of ınternational relations. According to Keohane and Nye, new situation had changed activities and roles of states majorly, but being basis actor feature of states was still preserving. A part of these debates is tried to answer in Kenneth Waltz’s studies because Waltz was one of the founder of neorealism. Approach of Kenneth Waltz is defined as neorealism and structural realism. Waltz claims that, states are fighting for one’s life in anarchical international order, and they want to maximize the power, but answer delayed by neoliberalists. According to neoliberalists, even if anarchy is subject, anarchy was not basis determinant over the cooperation of international, but there was similarity between neoliberalism and neorealism. Both of them accept that, international system is anarchic. Neoliberalists consider basis assumptions of classical liberalism approach, but basis purpose of neoliberalism; neoliberalism should be a theory aimed at to explain peace and security. Some theories of neoliberal determined that, even if they see ınternational system created order from sovereign national states, they said that, it is necessary to look international relations as pluralist and multi actor order. Some thinkers had used same means (pluralism and neoliberalism) because of that, but neoliberalism involves pluralism, idealism and Grotianism etc. for to have more extensive mean. On the other hand, neorealism-neoliberalism debate is conducted together with state centrism and transnationalism. According to transnationalism, international relations is not state centric because it had got out from being state centrism with entering new actors. Nye, Keohane and Vasquez alleged that, paradigm of state centric was requiring to change. The paradigm had got out from being state centric and only policy-maker with these discussions.

             Positivism-Post-positivism debate: it is one of the longest debates in International Relations, and it had shown up in the midst of 1980s. The debate was continuing the different farms nowadays. Many critical approaches of ınternational relations describe on their own as positivists. Robert Keohane had made a distinction between rationalists and reflectivists(the word is taken by Ramazan Gözen), and this distinction had been beginning of debate. On the other hand, Hollis and Smith made a distinction between understanding (Erklaren) and explanation (Verstehen). Hollis and Smith’s distinction showed us that, ınternational relations can examine different forms, and also if even assumptions about science do not reveal clearly, it is seen to fall into theoretical debates in foundations of ınternational relations. Last debate in Positivism period is about constructivism. When constructivism became the main topic of conversation first-time first-time, it tenders midway between rationalists and reflectivists, and had defended scientific idealism. First constructivism debate in ınternational relations had started with Alexander Wendt. According to Wendt, anarchy is not fate of states, and anarchy can be life style in peaceful environment by way of state actors. Wendt defined anarchy that, ‘anarchy is about what states mean from them.’ I mentioned above that, debate between Positivism and Post-positivism had started with distinction of rationalists and reflectivists. Keohane indicated neorealism and neoliberalism (rationalists) as main approach , and he put reflectivists against these. To sum up, post-positivist approaches relativize knowledge, break away from with objects or refute objects completely. The most remarkable thing is that every causal explanation boils down to positivism unambiguously. In other words, being of positivists was meaning being of scientific. The most important question about this debate is that ‘Is Post-positivism a critical theory or subsidiary positivist approach?’

Finally, I mentioned about discipline debates of international relations. Understanding these debates helps to develop us because watching film (such as; Lord of the Flies), talking subjects in nowadays etc. are about more hundred theories of international relations, but we do not say that hundred percent international relations theories are true because we clearly see that, new paradigm or theory can criticize or decay old paradigm or theory, so international relations theories should investigate better, and as Robert Cox says that, ‘theory is always for someone and for some purpose.’