Like Daniel Defoe, and later Marx, Mendels was powerfully impressed with the constellation of related innovations that emerged in eighteenth- century economies just emerging from mature mercantilism:
division of labor and specialization which appeared in England and France about a half century after the Treaty of Westphalia;
labor-saving technical devices that came into common industrial usage especially after about 1720 ( Defoe sets 1680 as the start of "a projecting age in which men set their heads to designing Engines and Mechanical Motion"); 3 and
expansion of markets beyond national political borders.
It was the combined effects of these three profound innovations that turned the engine of economic growth in early protoindustrial economies in Europe and England. Mendels' original theory of protoindustrialization included several predictions that anticipated subsequent industrialization and further modern economic growth:
protoindustrial population growth ultimately brought diminishing returns for both agriculture and industry; political pressures of a growing population prompted organizational and technological innovation in both sectors, which led to the factory system and industrialization, and to increasing pressures for continued expansion of national economies;
protoindustrialization concentrated economic profits and wealth in merchants, landlords, commercial farmers, and manufacturers; this was the "Accumulation of Capital" that stimulated Marx's analyses;
protoindustry required and generated new knowledge of industrial organization, commercial management, and work skills, as well as technologies and mechanical devices; these matured into the innovations that enervated full industrialization; and
protoindustrialization required and generated regional, technical, and industrial specializations that reflected both comparative advantage and noneconomic, political motivations, which generated political pressures on government for protection and support of specialist industries, and even individual firms.