Which was not an idea which descended from classical school?

One idea that did not descend from the classical school of economics is the concept of market imperfections. While classical economics emphasized the efficiency of markets and the idea of self-regulating forces, the recognition of factors such as monopolies, externalities, and information asymmetries emerged later, notably in the work of economists like Alfred Marshall and John Maynard Keynes. These ideas shifted the focus to the limitations and failures of markets, contrasting sharply with classical thought.