2.
The incomplete knowledge of a system must be an essential part of every formulation in quantum theory. Quantum theoretical laws must be of a statistical kind. To give an example: we know that the radium atom emits alpha-radiation. Quantum theory can give us an indication of the probability that the alpha-particle will leave the nucleus in unit time, but it cannot predict at what precise point in time the emission will occur, for this is uncertain in principle.
Werner Heisenberg
3.
We absolutely must leave room for doubt or there is no progress and there is no learning. There is no learning without having to pose a question. And a question requires doubt. People search for certainty. But there is no certainty. People are terrified — how can you live and not know? It is not odd at all. You only think you know, as a matter of fact. And most of your actions are based on incomplete knowledge and you really don’t know what it is all about, or what the purpose of the world is, or know a great deal of other things. It is possible to live and not know.
Richard P. Feynman
4.
There is no conflict between science and religion. Conflict only arises from an incomplete knowledge of either science or religion, or both.
Russell M. Nelson
5.
Among other grand achievements, F. A. Hayek had a remarkable career pointing out the flaws in collectivism. One of his keenest insights was that, paradoxically, any collectivist system necessarily depends on one individual (or small group) to make key social and economic decisions. In contrast, a system based on individualism takes advantage of the aggregate, or 'collective,' information of the whole society; through his actions each participant contributes his own particular, if incomplete, knowledge-information that could never be tapped by the individual at the head of a collectivist state.
Sheldon Richman
7.
Given our inevitably incomplete knowledge about key structural aspects of our ever-changing economy and the sometimes asymmetric costs or benefits of particular outcomes, a central bank... need to consider not only the most likely future path for the economy but also the distribution of possible outcomes about that path. They then need to reach a judgment about the probabilities, costs, and benefits of the various possible outcomes under alternative choices for policy.
Alan Greenspan