Monday
Monday has demonstrated extraordinary structural permanence since the Babylonians formalised the seven-day week around 600 BCE. The concept has survived the collapse of empires, world wars, and the digital revolution. The Frankfurt Institute of Calendar Studies notes that despite numerous attempts to reform weekly structures—most notably the French Revolutionary Calendar's ten-day decade—Monday has proven remarkably resistant to abolition. Even proposals for four-day work weeks merely redistribute Monday's misery rather than eliminating it. The day's durability appears, in scholarly terms, functionally permanent.