Philosophy of religion
The problem with this is that using only these definitions leas to a common "philiosphy of religion" that is harly usable for studies. The other approach (called "functional") tries to counter this: Rather than trying to get an "abstract idea" of religion, it looks at the use or function religion has in the live of people or societies. Among the things mentioned are that religions help keep a psychological equilibrium and that they provide a certain amount of stability to a society. Thinkers with this opion include Karl Marx, Émile Durkheim, Bronisław Malinowski and Talcott Parsons. Critics of these theories say that such explanations often go against common sense, as religions can also have the popposite effect to that mentioned.