One could write a history of science in reverse by assembling the solemn pronouncements of highest authority about what could not be done and could never happen. – Robert A. Heinlein

It is in the admission of ignorance and the admission of uncertainty that there is a hope for the continuous motion of human beings in some direction that doesnt get confined, permanently blocked, as it has so many times before in various periods in the history of man. – Richard P. Feynman