TOPIC: "By taking a look at literature in International Relations Theory, focus on these three traditions: realism, pluralism/liberalism, and cosmopolitanism/constructivism. There is much stability (no change) in these traditions, but there is also proof of growth and transformation through the years. By analyzing the history of all three, rank them, and explain which one has the most stability and which has had the most change."

After doing extensive research, I'm having problem distinguishing the difference between the three traditions, for they are extremely similar. Please help me identify which tradition has had the least change and the most change throughout history.