"Die Voraussetzungen des Sozialismus" (1899) was Bernstein's most significant work. Bernstein was principally concerned with refuting Karl Marx's predictions about the imminent and inevitable demise of capitalism and Marx's consequent laissez-faire policy which opposed ameliorative social interventions before the demise. Bernstein indicated simple facts, which he considered to be evidence that Marx's predictions were not being borne out while he noted that while the centralisation of capitalist industry was significant, it was not becoming wholescale and that the ownership of capital was becoming more and not less diffuse. Bernstein's analysis of agriculture, according to which Bernstein believed that land ownership was becoming less concentrated, was largely based on the work of Eduard David and was in its marshalling of facts impressive enough that even his Orthodox Marxist opponent Karl Kautsky acknowledged its value.