Much of Roman technology was lost because the collapse of state capacity and according administrative capacity rendered the balance of agrarian to non-agrarian workers unsustainable.
A high equilibrium, where the products of population centers supports and enhances the productivity of the agrarian surroundings while administrative pressure (like taxes) encourage the trade between the two: If the farmers need to pay taxes in coin, they need to sell surplus to merchants who ship it to cities to sell it. Conversely, the craftsmen producing iron plows, pottery and so on need coin too, so they sell tools, which the farmers buy to improve their yield. The state also buys services (like construction) and the elite buys luxuries, further creating jobs and fostering more technological development.
(Obviously, the elite skim a lot off the value produced by others - just because they did some good for others with it doesn’t mean they didn’t primarily do a lot of good for themselves.)
But when internal strife, plague, worsening climate, desperate invaders and identity politics all start breaking that machine, it’s hard to keep it from falling apart. And once the rural argarian production can no longer sustain the cities, the skills and crafts of the urbanites get lost.
Much of Roman technology was lost because the collapse of state capacity and according administrative capacity rendered the balance of agrarian to non-agrarian workers unsustainable.
A high equilibrium, where the products of population centers supports and enhances the productivity of the agrarian surroundings while administrative pressure (like taxes) encourage the trade between the two: If the farmers need to pay taxes in coin, they need to sell surplus to merchants who ship it to cities to sell it. Conversely, the craftsmen producing iron plows, pottery and so on need coin too, so they sell tools, which the farmers buy to improve their yield. The state also buys services (like construction) and the elite buys luxuries, further creating jobs and fostering more technological development.
(Obviously, the elite skim a lot off the value produced by others - just because they did some good for others with it doesn’t mean they didn’t primarily do a lot of good for themselves.)
But when internal strife, plague, worsening climate, desperate invaders and identity politics all start breaking that machine, it’s hard to keep it from falling apart. And once the rural argarian production can no longer sustain the cities, the skills and crafts of the urbanites get lost.