
Letter to Lord Fitzwilliam (9 April 1813), quoted in E. A. Smith, Lord Grey. 1764-1845 (Alan Sutton, 1996), pp. 174-175.
1810s
Source: The Demon-Haunted World : Science as a Candle in the Dark (1995), Ch. 2 : Science and Hope, p. 28
Letter to Lord Fitzwilliam (9 April 1813), quoted in E. A. Smith, Lord Grey. 1764-1845 (Alan Sutton, 1996), pp. 174-175.
1810s
Speech on the American Civil War, Town Hall, Newcastle upon Tyne (7 October 1862), quoted in The Times (9 October 1862), pp. 7-8.
1860s
The Value of Science (1955)
Context: The scientist has a lot of experience with ignorance and doubt and uncertainty, and this experience is of very great importance, I think. When a scientist doesn’t know the answer to a problem, he is ignorant. When he has a hunch as to what the result is, he is uncertain. And when he is pretty darn sure of what the result is going to be, he is still in some doubt. We have found it of paramount importance that in order to progress we must recognize our ignorance and leave room for doubt. Scientific knowledge is a body of statements of varying degrees of certainty — some most unsure, some nearly sure, but none absolutely certain. Now, we scientists are used to this, and we take it for granted that it is perfectly consistent to be unsure, that it is possible to live and not know. But I don’t know whether everyone realizes this is true. Our freedom to doubt was born out of a struggle against authority in the early days of science. It was a very deep and strong struggle: permit us to question — to doubt — to not be sure. I think that it is important that we do not forget this struggle and thus perhaps lose what we have gained.
The Cornerstone Speech (1861)
Context: The process of disintegration in the old Union may be expected to go on with almost absolute certainty if we pursue the right course. We are now the nucleus of a growing power which, if we are true to ourselves, our destiny, and high mission, will become the controlling power on this continent. To what extent accessions will go on in the process of time, or where it will end, the future will determine. So far as it concerns States of the old Union, this process will be upon no such principles of reconstruction as now spoken of, but upon reorganization and new assimilation. Such are some of the glimpses of the future as I catch them.
Source: Testimony: its Posture in the Scientific World (1859), p. 14
Five Essays on Liberty (2002), Two Concepts of Liberty (1958)
1920s, Science and the Modern World (1925)