Neoliberalism, liberal institutionalism or neo-liberal institutionalism is an advancement of liberal thinking. Some call the school of thought rational functionalism instead of liberal institutionalism. The debate has also been described as being between realism, institutionalism and structuralism. Generally, he is a supporter of neoliberal institutionalism and international cooperation. He names the opposite position transcendental institutionalism. Liberal institutionalism views international institutions as the main factor to avoid conflicts between nations. It has also been described as an "institutionalism of Machiavellian self-interest". Historical institutionalism is a predominant approach in research on the welfare state. He thus began an in-depth study of economics in the area of institutionalism. Numerous scholarly approaches have been described as being part of New institutionalism. Historical institutionalism is not a unified intellectual enterprise (see also new institutionalism). Institutionalism is frequently contrasted with Historical Institutionalism and Sociological Institutionalism. The term "Historical Institutionalism" was coined in the early 1990s. This version of institutionalism states that "history matters". Thus, the Old Institutionalism was unhelpful for comparative research and explanatory theory.