“In a multi-racial society, trust, understanding and tolerance are the cornerstones of peace and order.”

The Illuminatus! Trilogy (1975)

Max Fisher, "A fascinating map of the world’s most and least racially tolerant countries" https://www.washingtonpost.com/news/worldviews/wp/2013/05/15/a-fascinating-map-of-the-worlds-most-and-least-racially-tolerant-countries/ (15 May 2013), The Washington Post

2009, A New Beginning (June 2009)

Source: Ashtanga Yoga Primer, 1981, p.58

2000s, 2008, First Speech As London Mayor (May 3, 2008)

Speech delivered outside outside 10 Downing Street, announcing that he would resign as prime minister after British voters chose to leave the European Union in a referendum (June 24, 2016), see David Cameron's resignation speech in full http://www.cnn.com/2016/06/24/europe/david-cameron-full-resignation-speech/ (published by CNN)
2010s, 2016

Source: Institutions (1990), p. 39

Source: The New Party - (1961), Chapter 7, Program, p. 84

Vol. 1, Notes to the Chapters: Ch. 7, Note 4
The Open Society and Its Enemies (1945)
Context: The so-called paradox of freedom is the argument that freedom in the sense of absence of any constraining control must lead to very great restraint, since it makes the bully free to enslave the meek. The idea is, in a slightly different form, and with very different tendency, clearly expressed in Plato.
Less well known is the paradox of tolerance: Unlimited tolerance must lead to the disappearance of tolerance. If we extend unlimited tolerance even to those who are intolerant, if we are not prepared to defend a tolerant society against the onslaught of the intolerant, then the tolerant will be destroyed, and tolerance with them. — In this formulation, I do not imply, for instance, that we should always suppress the utterance of intolerant philosophies; as long as we can counter them by rational argument and keep them in check by public opinion, suppression would certainly be unwise. But we should claim the right to suppress them if necessary even by force; for it may easily turn out that they are not prepared to meet us on the level of rational argument, but begin by denouncing all argument; they may forbid their followers to listen to rational argument, because it is deceptive, and teach them to answer arguments by the use of their fists or pistols. We should therefore claim, in the name of tolerance, the right not to tolerate the intolerant. We should claim that any movement preaching intolerance places itself outside the law, and we should consider incitement to intolerance and persecution as criminal, in the same way as we should consider incitement to murder, or to kidnapping, or to the revival of the slave trade, as criminal.