 Morgenthau's belief in this regard is part of the reason he has been classified as a "classical realist" rather than a realist.Major theorists include E. H. Carr, Robert Gilpin, Charles P. Kindleberger, Stephen D. Krasner, Hans Morgenthau, Samuel P. Huntington, Kenneth Waltz, Stephen Walt, and John Mearsheimer.According to liberalism, individuals are basically good and capable of meaningful cooperation to promote positive change.