Aspects of philosopher, mathematician and social activist Bertrand Russell's views on society changed over nearly 80 years of prolific writing, beginning with his early work in 1896, until his death in February 1970.

Activism Political and social activism occupied much of Russell's time for most of his long life, which makes his prodigious and seminal writing on a wide range of technical and non-technical subjects all the more remarkable.

Russell remained politically active to the end of his life, writing to and exhorting world leaders and lending his name to various causes. Some maintain that during his last few years he gave his youthful followers too much license and that they used his name for some outlandish purposes of which a more attentive Russell would not have approved. There is evidence to show that he became aware of this when he fired his private secretary, Ralph Schoenman, then a young firebrand of the radical left.

Pacifism, war, and nuclear weapons Russell was originally a Liberal Imperialist but in 1901 converted to anti-imperialism, pacifism and a Pro-Boer standpoint with regards to the Second Boer War.The Autobiography of Bertrand Russell, George Allen and Unwin Ltd., 1971, p.146. He was later involved in the Union of Democratic Control.

He resisted specific wars on the grounds that they were contrary to the interests of civilisation, and thus immoral. On the other hand, his 1915 article on "The Ethics of War", he defended wars of colonisation on the same utilitarian grounds: he felt conquest was justified if the side with the more advanced civilisation could put the land to better use.

Russell's activism against British participation in World War I led to fines, a loss of freedom of travel within Britain, and the non-renewal of his fellowship at Trinity College, Cambridge, and he was eventually sentenced to prison in 1918 on the tenuous grounds that he had interfered in British foreign policy – he had argued that British workers should be wary of the United States Army, for it had experience in strike-breaking. He was released after serving six months, but was still closely supervised until the end of the war. Russell contended that "the abolition of private ownership of land and capital is a necessary step toward any world in which the nations are to live at peace with one another".

In 1943 Russell called his stance towards warfare "relative political pacifism" – he held that war was always a great evil, but in some particularly extreme circumstances (such as when Adolf Hitler threatened to take over Europe) it might be a lesser of multiple evils. In the years leading to World War II, he supported the policy of appeasement; but by 1940 he acknowledged that to preserve democracy, Hitler had to be defeated. This same reluctant value compromise was shared by his acquaintance A.A. Milne.

Russell consistently opposed the continued existence of nuclear weapons ever since their first use. However, on 20 November 1948, in a public speech at Westminster School, addressing a gathering arranged by the New Commonwealth, Russell shocked some observers with comments that seemed to suggest a preemptive nuclear strike on the Soviet Union might be justified. Russell apparently argued that the threat of war between the United States and the Soviet Union would enable the United States to force the Soviet Union to accept the Baruch Plan for international atomic energy control. (Earlier in the year he had written in the same vein to Walter W. Marseille.) Russell felt this plan "had very great merits and showed considerable generosity, when it is remembered that America still had an unbroken nuclear monopoly." (Has Man a Future?, 1961).

Nicholas Griffin of McMaster University, in his book The Selected Letters of Bertrand Russell: The Public Years, 1914–1970, interpreted Russell's wording as advocating not the actual use of the atom bomb, but merely its diplomatic use as a massive source of leverage over the actions of the Soviets.

Griffin's interpretation was disputed by Nigel Lawson; the former British Chancellor, who was present at the speech. Lawson claims it was quite clear that Russell was advocating an actual first strike, a view that is consistent with that reported by Hermann Bondi in Bondi's autobiography (Science, Churchill and Me, 1990, p60) recounting Russell's views from the time when Russell and Bondi were fellows of Trinity College in Cambridge. Whichever interpretation is correct, Russell later relented, instead arguing for mutual disarmament by the nuclear powers, possibly linked to some form of world government.

The Soviet interpretation seems to be negative. Izvestia dismissed Bertrand Russell, as “the English Fascist Malthusian Philosopher.” Hitler had “found worthy successors in England,” wrote one Soviet commentator. Fortunately, though, humanity was not compelled to take “the path of degeneration along which Fascist creatures like Bertrand Russell are leading it.”Wittner, Lawrence S. (1993). Struggle against the Bomb: One World or None. (Stanford University Press), p 294.

In 1955, Russell released the Russell-Einstein Manifesto, co-signed by Albert Einstein and nine other leading scientists and intellectuals, a document which led to the first of the Pugwash Conferences on Science and World Affairs in 1957. In 1957-58, Russell became the first president of the Campaign for Nuclear Disarmament, which advocated unilateral nuclear disarmament by Britain. He resigned two years later when the CND would not support civil disobedience, and formed the Committee of 100. In September 1961 he was imprisoned for a week under the Justices of the Peace Act 1361 for refusing to call off a huge ban-the-bomb demonstration at the Ministry of Defence organised by the Committee of 100. He served the sentence in the hospital of Brixton Prison.

During the Cuban Missile Crisis, Russell sent telegrams to US President John F. Kennedy, Soviet Premier Nikita Khrushchev, the UN Secretary-General U Thant and British Prime Minister Harold Macmillan. His telegrams were greatly critical of Kennedy, who he had already singled out earlier as "more dangerous than Hitler", and tolerant of Khrushchev. Khrushchev replied with a long letter, published by the Russian news agency ITAR-TASS, which was mainly addressed to Kennedy and the Western world.

Increasingly concerned about the potential danger to humanity arising from nuclear weapons and other scientific discoveries, he also joined with Einstein, Robert Oppenheimer, Joseph Rotblat and other eminent scientists of the day to establish the World Academy of Art and Science which was formally constituted in 1960.

The Bertrand Russell Peace Foundation and its publishing imprint Spokesman Books began work in 1963 to carry forward Russell's work for peace, human rights and social justice.

JFK Assassination Russell criticised the official account of the assassination of John F. Kennedy in "16 Questions on the Assassination", 1964. He was thanked in the acknowledgements section of Mark Lane's book Rush to Judgment for being "kind enough to read the manuscript and make suggestions", and after Simon & Schuster had declined to publish the book, Russell attempted to convince them otherwise. He also served as President of the British Who Killed Kennedy? Committee, in Russell's words the organisation was set up "for the purpose of making known the material [Lane] has uncovered and his further findings".

He is also thanked in Jim Garrison's On the Trail of the Assassins for "his early encouragement of my efforts".

Russell condemned the Warren Report as a "sorrily incompetent document" and said "it is clear that much is still being hidden". He argued that there were a number of "disturbing anomalies" regarding the assassination and that the Warren Commission had failed to deal with these doubts, that it instead "evades the facts". He believed that medical evidence had been altered and that "three contradictory official versions" had been put out.

Korea and Vietnam He began public opposition to US policy in Vietnam with a letter to The New York Times dated 28 March 1963. By the autumn of 1966, he had completed the manuscript War Crimes in Vietnam. Then, using the American justifications for the Nuremberg Trials, Russell, along with Jean-Paul Sartre, organised what he called an international War Crimes Tribunal, the Russell Tribunal.

Russell supported Korean nationalism, referring to North Koreans and South Koreans as "cousins".

Communism, anarchism and socialism Russell was, prior to being a socialist, a Georgist.Autobiography of Bertrand Russell

In 1914 he wrote to Lady Ottoline Morrell saying "It is clear the Socialists are the hope of the world". Russell expressed support for guild socialism."Review: Bertrand Russell on Socialism" He was also an admirer of Franklin Delano Roosevelt and Eduard Bernstein.

Russell expressed great hope in "the Communist experiment". However, when he visited the Soviet Union and met Vladimir Lenin in 1920, he was unimpressed with the system in place. On his return he wrote a critical tract, The Practice and Theory of Bolshevism. In later years he said of Lenin that he was "less impressed by Lenin than I expected to be" but also that he was a "great man". He considered him to be similar to a religious zealot as he said that Lenin believed "anything could be proved by quoting a text in Marx and he was quite incapable of supposing that there could be anything in Marx which wasn't right".

While in the Soviet Union he was "infinitely unhappy in this atmosphere – stifled by its utilitarianism, its indifference to love and beauty and the life of impulse." He was critical of Soviet Russia but still believed "that Communism is necessary to the world". Despite his criticism he nevertheless praised the Russian Revolution as "heroism" which had "fired men’s hopes in a way which was essential to the realization of Communism in the future" and that therefore "Bolshevism deserves the gratitude and admiration of all the progressive part of mankind"Preface to The Practice and Theory of Bolshevism (1920). George Allen & Unwin Ltd.

Later in his life, Russell completely denounced Marxism and communism, stating that:Russell, Bertrand (1956) "Why I am Not a Communist"

In the 1922 and 1923 general elections Russell stood as a Labour Party candidate in the Chelsea constituency, but only on the basis that he knew he was extremely unlikely to be elected in such a safe Conservative seat, and he was not on either occasion.

He was strongly critical of Joseph Stalin's regime, writing that Stalin was responsible for millions of deaths.Bertrand Russell, Unpopular Essays (1950), p.19, Simon and Schuster Between 1945 and 1947, together with A. J. Ayer and George Orwell, he contributed a series of articles to Polemic, a short-lived British "Magazine of Philosophy, Psychology, and Aesthetics" edited by the ex-Communist Humphrey Slater.Absent Minds: Intellectuals in Britain by Stefan Collini Oxford University Press, 2006 , 978-0-19-929105-2

Russell was a consistent enthusiast for democracy and world government, and he advocated the establishment of a democratic international government in some of the essays collected in In Praise of Idleness (1935), and also in Has Man a Future? (1961).

Russell wrote of Michael Bakunin that "we do not find in Bakunin's works a clear picture of the society at which he aimed, or any argument to prove that such a society could be stable." Russell did not believe that an anarchist society was "realizable" but that "it cannot be denied that Kropotkin presents it with extraordinary persuasiveness and charm."

Women's suffrage