In the middle ages there was a monk named Occam who later became famous for Occam’s razor. Actually this is a tool used in philosophical arguments. It in itself is not a philosophy. Although it must be well understood and carefully used in general it is a tool of parsimony (making things simple) or an attempt to choose the simpler hypothesis as more true.
Later, in the late nineteenth century there was a scientist named Charles Sanders Peirce who also came up with a tool used in philosophical arguments. Peirce was an American philosopher who is considered the founder of Pragmatism. Not only was he a practicing scientist, he was a logician. His tool used in philosophy was the pragmatic tool which asked if the hypothesis was "evidencially useful" in an attempt to choose a hypothesis which is truer. (Later pragmatism was reinterpreted by William James a psychologist and Dewey a sociologist which strayed from Peirce's original interpretation to an idea of practicality. Peirce took note and renamed his philosophical tool Pragmaticism rather than James/Dewey’s Pragmatism.) Let’s call Peirce's philosophical effort Peirce's razor and Peirce's razor akin to the scientific method.
Post Modernism has had a massive influence on Schools and modern life. Claiming subjectivity as a way around cold analysis and a world that is too complicated to understand, it has become a kind of avante-garde skeptism. It deconstructs everything like a child approaching a chess board where 2 masters are playing and the child wipes the board of all its pieces.
Yes the chess game is not perfect. One of the people playing the game is elite another is an imperialist. Yes the game originated as a game of war. Yet the game is a very good game of strategy. The game is very "evidencially useful" as a game of strategy.
Post Modernism is like an architect who doesn’t like the way a damn looks. Doesn't like the stones and doesn't like the aesthetics. Blow up the damn even as it floods the valley and all the homes.
There are many things that Post Modernism wants to sweep away. Yet many things are "evidencially useful" and pass Peirce's razor. Before sweeping everything away they need to create something that is "evidencially useful" that passes Peirce's razor to replace the thing they are sweeping away. Peirce's razor is a tool and is iterative and open to future changes in the attempt to make something more true similar to the scientific method. Post Modernism is a tool of destruction in philosophy and life which wants to sweep everything away with no real replacement.