Invention is here interpreted broadly as the production of knowledge. From the viewpoint of welfare economics, the determination of optimal resource … - Kenneth Arrow

It is this thinking which I think gives rise to the greatest tragedies of history, this sense of commitment to a past purpose which reinforces the original agreement precisely at a time when experience has shown that it must be reversed.

Ironically, the current conservative model explaining the supposed association of capitalism and democracy relates to the Marxist as a photographic negative to a positive. It too suggests that the political “superstructure” is determined by the “relations of production.” The conservative model contrasts the dispersion of power under capitalist democracy with its concentration under socialism. Political opposition requires resources. The multiplicity of capitalists implies that any dissenting voice can find some support. Under socialism, the argument goes, the controlling political faction can deny its opponents all resources and dismiss them from their employment.
This theoretical argument presupposes a monolithic state. It is something of a chicken-and-egg proposition. If the democratic legal tradition is strong, there are many sources of power in a modern state. Adding economic control functions may only increase the diversity of interests within the state and therefore alternative sources of power. It is notoriously harder for the government to regulate its own agencies than private firms. Socialism may easily offer as much pluralism as capitalism.
The overpowering force in all these arguments is the empirical evidence of the Soviet Union and the other Communist countries, and it is strong. But the contrary proposition, that capitalism is a positive safeguard for democracy, is hardly a reasonable inference from experience. The example of Nazi Germany shows that no amount of private enterprise prevents the rise of totalitarianism. Indeed, it is hard to see that capitalism formed a significant impediment. Nor is Nazi Germany unique; Fascist Italy, Franco’s Spain, and the recurrent Latin American dictatorships are illustrative counterexamples to the proposition that capitalism implies democracy.

Uncertainty means that we do not have a complete description of the world which we fully believe to be true.