Doubt and science
Peter Abelard (1079-1142): By doubting we come to inquiry, and through enquiry we perceive truth.
Richard Feynman (1918 – 1988): It is our responsibility as scientist, knowing the great progress and great value of a satisfactory philosophy of ignorance, the great progress that is the the fruit of freedom of thought, to proclaim the value of this freedom, to teach how doubt is not to be feared but welcomed and discussed, and to demand this freedom as our duty to all coming generations.