Murray Bookchin (January 14, 1921 - July 30, 2006) was an American social theorist, author, orator, historian, and political philosopher. A pioneer in the ecology movement, Bookchin formulated and developed the theory of social ecology within anarchist, libertarian socialist, and ecological thought. He was the author of two dozen books covering topics in politics, philosophy, history, urban affairs, and ecology. Among the most important were Our Synthetic Environment (1962), Post-Scarcity Anarchism (1971) and The Ecology of Freedom (1982).

Bookchin was critical of class-centered analysis of Marxism and simplistic anti-state forms of libertarianism and liberalism and wished to present what he saw as a more complex view of societies. In The Ecology of Freedom: The Emergence and Dissolution of Hierarchy, he says that:  My use of the word hierarchy in the subtitle of this work is meant to be provocative. There is a strong theoretical need to contrast hierarchy with the more widespread use of the words class and State; careless use of these terms can produce a dangerous simplification of social reality. To use the words hierarchy, class, and State interchangeably, as many social theorists do, is insidious and obscurantist. This practice, in the name of a "classless" or "libertarian" society, could easily conceal the existence of hierarchical relationships and a hierarchical sensibility, both of which-even in the absence of economic exploitation or political coercion-would serve to perpetuate unfreedom.  Bookchin also points to an accumulation of hierarchical systems throughout history that has occurred up to contemporary societies which tends to determine the human collective and individual psyche:  The objective history of the social structure becomes internalized as a subjective history of the psychic structure. Heinous as my view may be to modern Freudians, it is not the discipline of work but the discipline of rule that demands the repression of internal nature. This repression then extends outward to external nature as a mere object of rule and later of exploitation. This mentality permeates our individual psyches in a cumulative form up to the present day-not merely as capitalism but as the vast history of hierarchical society from its inception.Answer this question using a quote from the following article:

why did he feel that the using the word was insidious and obsurantist?
careless use of these terms can produce a dangerous simplification of social reality.