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Friday, January 2, 2026

Best of all possible worlds

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Best_of_all_possible_worlds

The phrase "the best of all possible worlds" (French: Le meilleur des mondes possibles; German: Die beste aller möglichen Welten) was coined by the German polymath and Enlightenment philosopher Gottfried Leibniz in his 1710 work Essais de Théodicée sur la bonté de Dieu, la liberté de l'homme et l'origine du mal (Essays of Theodicy on the Goodness of God, the Freedom of Man and the Origin of Evil), more commonly known simply as the Theodicy. The claim that the actual world is the best of all possible worlds is the central argument in Leibniz's theodicy, or his attempt to solve the problem of evil.

Leibniz

In Leibniz's works, the argument about the best of all possible worlds appears in the context of his theodicy, a word that he coined by combining the Greek words Theos, 'God', and dikē, 'justice'. Its object was to solve the problem of evil, that is, to reconcile the existence of evil and suffering in the world with the existence of a perfectly good, all-powerful and all-knowing God, who would seem required to prevent it; as such, the name comes from Leibniz's conceiving of the project as the vindication of God's justice, namely against the charges of injustice brought against him by such evils. Proving that this is the best of all possible worlds would dispel such charges by showing that, no matter how it may intuitively appear to us from our limited point of view, any other world – such as, namely, one without the evils which trouble our lives – would, in fact, have been worse than the current one, all things considered.

Leibniz's argument for this conclusion may be gathered from the paragraphs 53–55 of his Monadology, which run as follows:

53. Now as there are an infinity of possible universes in the ideas of God, and but one of them can exist, there must be a sufficient reason for the choice of God which determines him to select one rather than another.
54. And this reason is to be found only in the fitness or in the degree of perfection which these worlds possess, each possible thing having the right to claim existence in proportion to the perfection which it involves.
55. This is the cause for the existence of the greatest good; namely, that the wisdom of God permits him to know it, his goodness causes him to choose it, and his power enables him to produce it.

Since this is a very compact exposition, the remainder of this section will explain the argument in more words. While the text refers to "possible universes", this article will often adopt the more common usage "possible worlds", which refers to the same thing, which is explained next. As Leibniz said in the Theodicy, this term should not be misunderstood as referring only to a single planet or reality, since it refers to the sum of everything that exists:

I call 'World' the whole succession and the whole agglomeration of all existent things, lest it be said that several worlds could have existed in different times and different places.

Possible worlds

Possible worlds, according to Leibniz's theory, are combinations of beings which are possible together, that is, compossible.

A being is possible, for Leibniz, when it is logically possible, i.e., when its definition involves no contradiction.^[7] For example, a married bachelor is impossible because a "bachelor" is, by definition, an unmarried man, which contradicts "married". But a unicorn, if defined as a horse with a horn, contains no contradiction, so that such a being is possible, even if none exist in the actual world.

Beings are possible together, in turn, when they do not enter into contradiction with each other. For instance, it is logically possible that a meteor might have fallen from the sky onto Wikipedia founder Jimmy Wales's head soon after he was born, killing him. But it is not logically possible that what happens in a given world (e.g. that Jimmy Wales founded Wikipedia) also does not happen in the same world (i.e. that Jimmy Wales did not found Wikipedia). While both of these events are logically possible in themselves, they are not logically possible together, or compossible – so, they cannot form part of the same possible world.

Leibniz claims in §53, then, that there are infinitely many of these possible worlds, or combinations of compossible beings, in the ideas of God. These are the worlds which God could possibly bring into existence, since not even God, according to Leibniz, could create a world which contains a contradiction.

Sufficient reason

Although God cannot create a self-contradictory world, he is all-powerful and all-knowing, as emphasized in §55. He cannot be prevented from creating a world by not knowing about it, or by lacking the power to make it. Given these assumptions, it might seem that God could create just any one of the worlds. And since there are infinitely many possible worlds, it might seem that, just as there is no greatest among the infinitely many numbers, there is no best of the possible worlds.

Leibniz rejects these possibilities by appealing to the Principle of Sufficient Reason (PSR), a central principle of his philosophical system. This principle, which he was the first to name, was once described by him as the principle "that nothing happens without a reason"; in the Monadology, which is the work at hand, he described it as follows:

31. Our reasoning is based upon two great principles: first, that of contradiction, by means of which we decide that to be false which involves contradiction and that to be true which contradicts or is opposed to the false. 32. And second, the principle of sufficient reason, in virtue of which we believe that no fact can be real or existing and no statement true unless it has a sufficient reason why it should be thus and not otherwise. Most frequently, however, these reasons cannot be known by us.

Since Leibniz adopted his principle, he could not admit that God chose to create this world rather than another – that God's choice was "thus and not otherwise" – for no reason, or "arbitrarily".

Leibniz then claims that the only possible reason for the choice between these possible worlds is "the fitness or the degree of perfection" which they possess – i.e., the quality which makes worlds better than others, so that the world with the greatness "fitness" or "perfection" is the best one. As the philosophers Michael Murray and Sean Greenberg interpreted it, this claim may be understood by the consideration that basing the choice on any other quality about the worlds would have been arbitrary, contrary to the PSR.

Leibniz claims that God's choice is caused not only by its being the most reasonable, but also by God's perfect goodness, a traditional claim about God which Leibniz accepted. As Leibniz says in §55, God's goodness causes him to produce the best world. Hence, the best possible world, or "greatest good" as Leibniz called it in this work, must be the one that exists.

Evil in the best world

Leibniz, following a long metaphysical tradition that goes back at least to Augustine, conceived of the perfection of the universe as its "metaphysical goodness", which is identical with "being", or "reality". The best world is the one with the greatest "degree of reality", the greatest "quantity of essence", the greatest "perfection" and "intelligibility". According to this tradition, "evil, though real, is not a 'thing', but rather a direction away from the goodness of the One"; evil is the absence of good, and accordingly, it is technically wrong to say that God created evil, properly speaking. Rather, he created a world which was imperfectly good.

According to the privation theory of evil, all examples of evils are analysed as consisting in the absence of some good that ought to be there, or is natural to a thing – for instance, disease is the absence of health, blindness is the absence of sight, and vice is the absence of virtue. Evil may be said to exist in the same way the hole of a donut exists: the donut was created, but the hole itself was not made, it was just never filled in – it is an absence. And just as the hole could not exist without the donut, evil is parasitic upon good, since it is the corruption of a good nature. "God is infinite, and the devil is limited; the good may and does go to infinity, while evil has its bounds."

Leibniz did, nevertheless, concede that God has created a world with evil in it, and could have created a world without it. He claimed, however, that the existence of evil does not necessarily mean a worse world, so that this is still the best world that God could have made. In fact, Leibniz claimed that the presence of evil may make for a better world, insofar as "it may happen that the evil is accompanied by a greater good" – as he said, "an imperfection in the part may be required for a perfection in the whole".

In light of the conceptual tools that have already been explained, this claim may be phrased as stating that there are goods in the universe which would not be compossible with the prevention of certain evils. This claim, which may seem counterintuitive, was elucidated by Leibniz in various ways. For instance, in the Theodicy, he used certain analogies to emphasize how the contrast provided by evil may increase the good, and make it more discernible:

Use has ever been made of comparisons taken from the pleasures of the senses when these are mingled with that which borders on pain, to prove that there is something of like nature in intellectual pleasures. A little acid, sharpness or bitterness is often more pleasing than sugar; shadows enhance colours; and even a dissonance in the right place gives relief to harmony. We wish to be terrified by rope-dancers on the point of falling and we wish that tragedies shall well-nigh cause us to weep. Do men relish health enough, or thank God enough for it, without having ever been sick? And is it not most often necessary that a little evil render the good more discernible, that is to say, greater?

In other works, Leibniz also used his broader theory that there are no "purely extrinsic denominations" – everything that may be said about something is essential to it. So, according to Leibniz, it is technically wrong to say that "I would be better off" in another possible world: each individual is world-bound, so that, if God had not actualized this specific world, I would not exist at all. And even if, due to my great personal suffering, I should think that it would be better for me to not exist, it would nevertheless be worse for the rest of the universe, since this world is the best possible world, as was proved.

Uses outside of theodicy

Leibniz also applied his theory of the best of all possible worlds to solve the problem of induction. Out of all possible worlds, God has chosen "the most perfect, that is to say, the one which is at the same time the simplest in hypotheses and the richest in phenomena". (Discourse on Metaphysics, §6) This justifies human beings in choosing to believe, out of the available theories, those which are simplest and have the most explanatory power.

Before Leibniz

The philosopher Calvin Normore has claimed that, according to the Stoics, this is the best of all possible worlds, and that this opinion was shared by Peter Abelard.

Avicenna argued that divine providence ensures that this is the best of all possible worlds.

Thomas Aquinas, in article 6 of question 25 of the first part of his Summa Theologiae, had affirmed that God can always make better what he has made, but only by making more things; "the present creation being supposed, cannot be better."

After Leibniz

18th century

Following the devastating Lisbon Earthquake (1 November 1755), which occurred decades after the publication of the Theodicy (1710), Leibniz's philosophical optimism and theodicy incurred considerable criticism both from his fellow Enlightenment philosophers and from Christian theologians. Critics of Leibniz argue that the world contains an amount of suffering too great to permit belief in philosophical optimism.

The claim that we live in the best of all possible worlds drew scorn most notably from Voltaire, who lampooned it in his comic novella Candide by having the character Dr. Pangloss (a parody of Leibniz and Maupertuis) repeat it like a mantra when great catastrophes keep happening to him and the titular protagonist. Derived from this character, the adjective "Panglossian" describes a person who believes that the actual world is the best possible one, or is otherwise excessively optimistic.

19th century

The physiologist Emil du Bois-Reymond, in his "Leibnizian Thoughts in Modern Science" (1870), wrote that Leibniz thought of God as a mathematician:

As is well known, the theory of the maxima and minima of functions was indebted to him for the greatest progress through the discovery of the method of tangents. Well, he conceives God in the creation of the world like a mathematician who is solving a minimum problem, or rather, in our modern phraseology, a problem in the calculus of variations – the question being to determine among an infinite number of possible worlds, that for which the sum of necessary evil is a minimum.

Du Bois-Reymond believed that Charles Darwin supported a version of Leibniz's perfect world, since every organism can be understood as relatively adapted to its environment at any point in its evolution.

Arthur Schopenhauer argued, contrary to Leibniz, that our world must be the worst of all possible worlds, because if it were only a little worse, it could not continue to exist.

20th century

The Theodicy was deemed illogical by the philosopher Bertrand Russell. Russell argues that moral and physical evil must result from metaphysical evil (imperfection). But imperfection is merely limitation; if existence is good, as Leibniz maintains, then the mere existence of evil requires that evil also be good. In addition, libertarian Christian theology (not related to political libertarianism) defines sin as not necessary but contingent, the result of free will. Russell maintains that Leibniz failed to logically show that metaphysical necessity (divine will) and human free will are not incompatible or contradictory. He also claims that when Leibniz analyzes the propositions, he is "ambiguous or doubtful..." (O'Briant). That is, Leibniz does not sound sure, and is unsure of himself when he writes his premises; and they do not work together without making Leibniz sound unsure of himself.

21st century

The philosopher Alvin Plantinga criticized Leibniz's theodicy by arguing that there probably is not such a thing as the best of all possible worlds, since one can always conceive a better world, such as a world with one more morally righteous person.

The philosopher William C. Lane defended Leibniz from Plantinga's criticism and also claimed that Leibniz's theory has pandeistic consequences:

If divine becoming were complete, God's kenosis – God's self-emptying for the sake of love – would be total. In this pandeistic view, nothing of God would remain separate and apart from what God would become. Any separate divine existence would be inconsistent with God's unreserved participation in the lives and fortunes of the actualized phenomena."

Leibniz's theodicy has been defended by Justin Daeley, who argues that God must create the best, and James Franklin, who argues that goods and evils in creation are interconnected with mathematical necessity and hence cannot be separated by divine power.

Left-wing politics

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Left-wing_politics

Left-wing politics or leftism is the range of political ideologies that support and seek to achieve social equality and egalitarianism, often in opposition to social hierarchy either as a whole, or to certain social hierarchies. Left-wing politics typically involve a concern for those in society whom its adherents perceive as disadvantaged relative to others as well as a belief that there are unjustified inequalities that need to be reduced or abolished, through radical means that change the nature of the society they are implemented in.

Ideologies considered to be left-wing vary greatly depending on the placement along the political spectrum in a given time and place. At the end of the 18th century, upon the founding of the first liberal democracies, the term Left was used to describe liberalism in the United States and republicanism in France, supporting a lesser degree of hierarchical decision-making than the right-wing politics of the traditional conservatives and monarchists. In modern politics, the term Left typically applies to ideologies and movements to the left of classical liberalism, supporting some degree of democracy in the economic sphere.

Today, ideologies such as social liberalism and social democracy are considered to be centre-left, while the Left is typically reserved for movements more critical of capitalism, including the labour movement, socialism, anarchism, communism, Marxism, Leninism and syndicalism, each of which rose to prominence in the 19th and 20th centuries. In addition, the term left-wing has also been applied to a broad range of culturally liberal and progressive social movements, including the civil rights movement, feminist movement, LGBTQ rights movement, abortion-rights movements, multiculturalism, anti-war movement, and environmental movement, as well as a wide range of political parties.

Name

Within the left–right political spectrum, left and right were coined during the French Revolution, referring to the seating arrangement in the French National Assembly as the political groups opposed to the royal veto privilege (Montagnard and Jacobin deputies from the Third Estate) generally sat to the left of the presiding member's chair in parliament while the ones in favour of the royal veto privilege sat on its right.

Usage of the term left became more prominent after the restoration of the French monarchy in 1815, when it was applied to the Independents. The word wing was first appended to left and right factions in the late 19th century, usually with disparaging intent, and left-wing was applied to those who were unorthodox in their religious or political views.

Positions

Economics

Left-leaning economic beliefs range from Keynesian economics and the welfare state through industrial democracy and the social market to the nationalisation of the economy and central planning, to the anarcho-syndicalist advocacy of a council-based and self-managed anarchist communism. Left-wing politics are typically associated with popular or state control of major political and economic institutions. During the Industrial Revolution, leftists supported trade unions. At the beginning of the 20th century, many leftists advocated strong government intervention in the economy.

According to emeritus professor of economics Barry Clark, supporters of left-wing politics "claim that human development flourishes when individuals engage in cooperative, mutually respectful relations that can thrive only when excessive differences in status, power, and wealth are eliminated."

Leftists continue to criticise the perceived exploitative nature of globalisation, the "race to the bottom" and unjust lay-offs and exploitation of workers. In the last quarter of the 20th century, the belief that the government (ruling in accordance with the interests of the people) ought to be directly involved in the day-to-day workings of an economy declined in popularity amongst the centre-left, especially social democrats who adopted the Third Way.

Other leftists believe in Marxian economics, named after the economic theories of Karl Marx. Some distinguish Marx's economic theories from his political philosophy, arguing that Marx's approach to understanding the economy is independent of his advocacy of revolutionary socialism or his belief in the inevitability of a proletarian revolution.Marxian economics do not exclusively rely on Marx and draw from a range of Marxist and non-Marxist sources. The dictatorship of the proletariat and workers' state are terms used by some Marxists, particularly Leninists and Marxist–Leninists, to describe what they see as a temporary state between the capitalist state of affairs and a communist society. Marx defined the proletariat as salaried workers, in contrast to the lumpenproletariat, who he defined as the outcasts of society such as beggars, tricksters, entertainers, buskers, criminals and prostitutes. The political relevance of farmers has divided the left. In Das Kapital, Marx scarcely mentioned the subject. Mikhail Bakunin thought the lumpenproletariat was a revolutionary class, while Mao Zedong believed that it would be rural peasants, not urban workers, who would bring about the proletarian revolution.

Left-libertarians, anarchists and libertarian socialists believe in a decentralised economy run by trade unions, workers' councils, cooperatives, municipalities and communes, opposing both state and private control of the economy, preferring social ownership and local control in which a nation of decentralised regions is united in a confederation. The global justice movement, also known as the anti-globalisation movement and the alter-globalisation movement, protests against corporate economic globalisation due to its negative consequences for the poor, workers, the environment, and small businesses.

Leftists generally believe in innovation in various technological and philosophical fields and disciplines to help causes they support.

Environment

One of the foremost left-wing advocates was Thomas Paine, one of the first individuals since left and right became political terms to describe the collective human ownership of the world, which he speaks of in Agrarian Justice. As such, most of left-wing thought and literature regarding environmentalism stems from this duty of ownership and the aforementioned form of cooperative ownership means that humanity must take care of the Earth.This principle is reflected in much of the historical left-wing thought and literature that came afterwards, although there were disagreements about what this entailed. Karl Marx and the early socialist philosopher and scholar William Morris had a concern for environmental matters. According to Marx, "[e]ven an entire society, a nation, or all simultaneously existing societies taken together, are not the owners of the earth. They are simply its possessors, its beneficiaries, and have to bequeath it in an improved state to succeeding generations". Following the Russian Revolution, environmental scientists such as revolutionary Alexander Bogdanov and the Proletkult organisation made efforts to incorporate environmentalism into Bolshevism and "integrate production with natural laws and limits" in the first decade of Soviet rule, before Joseph Stalin attacked ecologists and the science of ecology, purged environmentalists and promoted the pseudoscience of Trofim Lysenko during his rule up until his death in 1953.Similarly, Mao Zedong rejected environmentalism and believed that based on the laws of historical materialism, all of nature must be put into the service of revolution.

From the 1970s onwards, environmentalism became an increasing concern of the left, with social movements and several unions campaigning on environmental issues and causes. In Australia, the left-wing Builders Labourers Federation, led by the communist Jack Mundy, united with environmentalists to place green bans on environmentally destructive development projects. Several segments of the socialist and Marxist left consciously merged environmentalism and anti-capitalism into an eco-socialist ideology. Barry Commoner articulated a left-wing response to The Limits to Growth model that predicted catastrophic resource depletion and spurred environmentalism, postulating that capitalist technologies were the key cause responsible for environmental degradation, as opposed to human population pressures. Environmental degradation can be seen as a class or equity issue, as environmental destruction disproportionately affects poorer communities and countries.

Several left-wing or socialist groupings have an overt environmental concern and several green parties contain a strong socialist presence. The Green Party of England and Wales features an eco-socialist group, the Green Left, which was founded in June 2005. Its members held several influential positions within the party, including both the former Principal Speakers Siân Berry and Derek Wall, himself an eco-socialist and Marxist academic. In Europe, several green left political parties such as the European United Left–Nordic Green Left combine traditional social-democratic values such as a desire for greater economic equality and workers rights with demands for environmental protection. Democratic socialist Bolivian president Evo Morales has traced environmental degradation to capitalist consumerism, stating that "[t]he Earth does not have enough for the North to live better and better, but it does have enough for all of us to live well". James Hansen, Noam Chomsky, Raj Patel, Naomi Klein, The Yes Men and Dennis Kucinich hold similar views.

In climate change mitigation, the Left is also divided over how to effectively and equitably reduce carbon emissions as the center-left often advocates a reliance on market measures such as emissions trading and a carbon tax while those further to the left support direct government regulation and intervention in the form of a Green New Deal, either alongside or instead of market mechanisms.

Nationalism, anti-imperialism and anti-nationalism

The question of nationality, imperialism and nationalism has been a central feature of political debates on the Left. During the French Revolution, nationalism was a key policy of the Republican Left. The Republican Left advocated for civic nationalism and argued that the nation is a "daily plebiscite" formed by the subjective "will to live together". Related to revanchism, the belligerent will to take revenge against Germany and retake control of Alsace-Lorraine, nationalism was sometimes opposed to imperialism. In the 1880s, there was a debate between leftists such as the Radical Georges Clemenceau, the Socialist Jean Jaurès and the nationalist Maurice Barrès, who argued that colonialism diverted France from liberating the "blue line of the Vosges", in reference to Alsace-Lorraine; and the "colonial lobby" such as Jules Ferry of the Moderate Republicans, Léon Gambetta of the Republicans and Eugène Etienne, the president of the Parliamentary Colonial Group. After the antisemitic Dreyfus Affair in which officer Alfred Dreyfus was falsely convicted of sedition and exiled to a penal colony in 1894 before being exonerated in 1906, nationalism in the form of Boulangism increasingly became associated with the far-right.

The Marxist social class theory of proletarian internationalism asserts that members of the working class should act in solidarity with working people in other countries in pursuit of a common class interest, rather than only focusing on their own countries. Proletarian internationalism is summed up in the slogan: "Workers of the world, unite!", the last line of The Communist Manifesto. Union members had learned that more members meant more bargaining power. Taken to an international level, leftists argued that workers should act in solidarity with the international proletariat in order to further increase the power of the working class. Proletarian internationalism saw itself as a deterrent against war and international conflicts, because people with a common interest are less likely to take up arms against one another, instead focusing on fighting the bourgeoisie as the ruling class. According to Marxist theory, the antonym of proletarian internationalism is bourgeois nationalism. Some Marxists, together with others on the left, view nationalism, racism (including antisemitism) and religion as divide and conquer tactics used by the ruling classes to prevent the working class from uniting against them in solidarity with one another. Left-wing movements have often taken up anti-imperialist positions. Anarchism has developed a critique of nationalism that focuses on nationalism's role in justifying and consolidating state power and domination. Through its unifying goal, nationalism strives for centralisation (both in specific territories and in a ruling elite of individuals) while it prepares a population for capitalist exploitation. Within anarchism, this subject has been extensively discussed by Rudolf Rocker in his book titled Nationalism and Culture and by the works of Fredy Perlman such as Against His-Story, Against Leviathan and The Continuing Appeal of Nationalism.

The failure of revolutions in Germany and Hungary in the 1918–1920 years ended Bolshevik hopes for an imminent world revolution and led to the promotion of the doctrine of socialism in one country by Joseph Stalin. In the first edition of his book titled Osnovy Leninizma (Foundations of Leninism, 1924), Stalin argued that revolution in one country is insufficient. By the end of that year in the second edition of the book, he argued that the "proletariat can and must build the socialist society in one country". In April 1925, Nikolai Bukharin elaborated on the issue in his brochure titled Can We Build Socialism in One Country in the Absence of the Victory of the West-European Proletariat?, whose position was adopted as state policy after Stalin's January 1926 article titled On the Issues of Leninism (К вопросам ленинизма) was published. This idea was opposed by Leon Trotsky and his supporters, who declared the need for an international "permanent revolution" and condemned Stalin for betraying the goals and ideals of the socialist revolution. Various Fourth Internationalist groups around the world who describe themselves as Trotskyist see themselves as standing in this tradition while Maoist China formally supported the theory of socialism in one country.

European social democrats strongly support Europeanism and supranational integration within the European Union, although there is a minority of nationalists and Eurosceptics on the left. Several scholars have linked this form of left-wing nationalism to the pressure generated by economic integration with other countries, often encouraged by neoliberal free trade agreements. This view is sometimes used to justify hostility towards supranational organisations. Left-wing nationalism can also refer to any form of nationalism which emphasises a leftist working-class populist agenda that seeks to overcome exploitation or oppression by other nations. Many Third World anti-colonialist movements have adopted leftist and socialist ideas. Third-Worldism is a tendency within leftist thought that regards the division between First World and Second World developed countries and Third World developing countries as being of high political importance. This tendency supports decolonisation and national liberation movements against imperialism by capitalists. Third-Worldism is closely connected with African socialism, Latin American socialism, Maoism, pan-Africanism and pan-Arabism. Several left-wing groups in the developing world such as the Zapatista Army of National Liberation in Mexico, the Abahlali baseMjondolo in South Africa and the Naxalites in India have argued that the First World and the Second World Left takes a racist and paternalistic attitude towards liberation movements in the Third World.

Religion

The original French Left was firmly anti-clerical, strongly opposing the influence of the Roman Catholic Church and supporting atheism and the separation of church and state, ushering in a policy known as laïcité. Karl Marx asserted that "religion is the sigh of the oppressed creature, the heart of a heartless world, and the soul of soulless conditions. It is the opium of the people". In Soviet Russia, the Bolsheviks under Vladimir Lenin originally embraced an ideological principle which professed that all religion would eventually atrophy and resolved to eradicate organised Christianity and other religious institutions. In 1918, 10 Russian Orthodox hierarchs were summarily executed by a firing squad, and children were deprived of any religious education outside of the home.

Today in the Western world, those on the Left generally support secularisation and the separation of church and state. However, religious beliefs have also been associated with many left-wing movements such as the progressive movement, the Social Gospel movement, the civil rights movement, the anti-war movement, the anti-capital punishment movement and Liberation Theology. Early utopian socialist thinkers such as Robert Owen, Charles Fourier and the Comte de Saint-Simon based their theories of socialism upon Christian principles. Other common leftist concerns such as pacifism, social justice, racial equality, human rights and the rejection of capitalism and excessive wealth can be found in the Bible.

In the late 19th century, the Protestant Social Gospel movement arose in the United States which integrated progressive and socialist thought with Christianity through faith-based social activism. Other left-wing religious movements include Buddhist socialism, Jewish socialism and Islamic socialism. There have been alliances between the left and anti-war Muslims, such as the Respect Party and the Stop the War Coalition in Britain. In France, the left has been divided over moves to ban the hijab from schools, with some leftists supporting a ban based on the separation of church and state in accordance with the principle of laïcité and other leftists opposing the prohibition based on personal and religious freedom.

Social progressivism and counterculture

Social progressivism is another common feature of modern leftism, particularly in the United States, where social progressives played an important role in the abolition of slavery, the enshrinement of women's suffrage in the United States Constitution, and the protection of civil rights, LGBTQ rights, women's rights and multiculturalism. Progressives have both advocated for alcohol prohibition legislation and worked towards its repeal in the mid to late 1920s and early 1930s. Current positions associated with social progressivism in the Western world include strong opposition to the death penalty, torture, mass surveillance, and the war on drugs, and support for abortion rights, cognitive liberty, LGBTQ rights including legal recognition of same-sex marriage, same-sex adoption of children, the right to change one's legal gender, distribution of contraceptives, and public funding of embryonic stem-cell research. The desire for an expansion of social and civil liberties often overlaps that of the libertarian movement. Public education was a subject of great interest to groundbreaking social progressives such as Lester Frank Ward and John Dewey, who believed that a democratic society and system of government was practically impossible without a universal and comprehensive nationwide system of education.

Various counterculture and anti-war movements in the 1960s and 1970s were associated with the New Left. Unlike the earlier leftist focus on labour union activism and a proletarian revolution, the New Left instead adopted a broader definition of political activism commonly called social activism. The New Left in the United States is associated with the hippie movement, mass protest movements on school campuses and a broadening of focus from protesting class-based oppression to include issues such as gender, race and sexual orientation. The British New Left was an intellectually driven movement which attempted to correct the perceived errors of the Old Left. The New Left opposed prevailing authoritarian structures in society which it designated as "The Establishment" and became known as the "Anti-Establishment". The New Left did not seek to recruit industrial workers en masse, but instead concentrated on a social activist approach to organization, convinced that they could be the source for a better kind of social revolution. This view has been criticised by several Marxists, especially Trotskyists, who characterised this approach as "substitutionism" which they described as a misguided and non-Marxist belief that other groups in society could "substitute" for and "replace" the revolutionary agency of the working class.

Many early feminists and advocates of women's rights were considered a part of the Left by their contemporaries. Feminist pioneer Mary Wollstonecraft was influenced by Thomas Paine. Many notable leftists have been strong supporters of gender equality such as Marxist philosophers and activists Rosa Luxemburg, Clara Zetkin and Alexandra Kollontai, anarchist philosophers and activists such as Virginia Bolten, Emma Goldman and Lucía Sánchez Saornil and democratic socialist philosophers and activists such as Helen Keller and Annie Besant. However, Marxists such as Rosa Luxemburg, Clara Zetkin, and Alexandra Kollontai, who are supporters of radical social equality for women and have rejected and opposed liberal feminism because they considered it to be a capitalist bourgeois ideology. Marxists were responsible for organising the first International Working Women's Day events.

The women's liberation movement is closely connected to the New Left and other new social movements which openly challenged the orthodoxies of the Old Left. Socialist feminism as exemplified by the Freedom Socialist Party and Radical Women and Marxist feminism, spearheaded by Selma James, saw themselves as a part of the Left that challenges male-dominated and sexist structures within the Left. The connection between left-wing ideologies and the struggle for LGBTQ rights also has an important history. Prominent socialists who were involved in early struggles for LGBTQ rights include Edward Carpenter, Oscar Wilde, Harry Hay, Bayard Rustin and Daniel Guérin, among others. The New Left is also strongly supportive of LGBTQ rights and liberation, having been instrumental in the founding of the LGBTQ rights movement in the aftermath of the Stonewall Riots of 1969. Contemporary leftist activists and socialist countries such as Cuba are actively supportive of LGBTQ+ people and are involved in the struggle for LGBTQ+ rights and equality.

History

The 5 May 1789 opening of the Estates General of 1789 in Versailles

Throughout the 19th century, the main line dividing Left and Right was between supporters of the French republic and those of the monarchy's privileges. The June Days uprising during the Second Republic was an attempt by the Left to re-assert itself after the 1848 Revolution, but only a small portion of the population supported this.

In the mid-19th century, nationalism, socialism, democracy and anti-clericalism became key features of the French Left. After Napoleon III's 1851 coup and the subsequent establishment of the Second Empire, Marxism began to rival radical republicanism and utopian socialism as a force within left-wing politics. The influential Communist Manifesto by Karl Marx and Friedrich Engels, published amidst the wave of revolutions of 1848 across Europe, asserted that all of human history is defined by class struggle. They predicted that a proletarian revolution would eventually overthrow bourgeois capitalism and create a stateless, moneyless and classless communist society. It was in this period that the word wing was appended to both Left and Right.

The International Workingmen's Association (1864–1876), sometimes called the First International, brought together delegates from many different countries, with many different views about how to reach a classless and stateless society. Following a split between supporters of Marx and Mikhail Bakunin, anarchists formed the Saint-Imier International and later the International Workers' Association (IWA–AIT). The Second International (1888–1916) became divided over the issue of World War I. Those who opposed the war, among them Vladimir Lenin and Rosa Luxemburg, saw themselves as further to the left.

In the United States, leftists such as social liberals, progressives and trade unionists were influenced by the works of Thomas Paine, who introduced the concept of asset-based egalitarianism which theorises that social equality is possible by a redistribution of resources. After the Reconstruction era in the aftermath of the American Civil War, the phrase "the Left" was used to describe those who supported trade unions, the civil rights movement and the anti-war movement. More recently, left-wing and right-wing have often been used as synonyms for the Democratic and Republican parties, or as synonyms for liberalism and conservatism, respectively.

During the 20th century, war resulted in a dramatic intensification of the pace of social changes, and was a crucial catalyst for the growth of left-wing politics. Since the Right was populist, both in the Western and the Eastern Bloc, anything viewed as avant-garde art was called leftist across Europe, thus the identification of Picasso's Guernica as "leftist" in Europeand the condemnation of the Russian composer Shostakovich's opera (The Lady Macbeth of Mtsensk District) in Pravda as follows: "Here we have 'leftist' confusion instead of natural, human music".

Types

The spectrum of left-wing politics ranges from centre-left to far-left or ultra-left. The term centre-left describes a position within the political mainstream that accepts capitalism and a market economy. The terms far-left and ultra-left are used for positions that are more radical, more strongly rejecting capitalism and mainstream representative democracy, instead advocating for a socialist society based on economic democracy and direct democracy, representing economic, political and social democracy. The centre-left includes social democrats, social liberals, progressives and greens. Centre-left supporters accept market allocation of resources in a mixed economy with an empowered public sector and a thriving private sector. Centre-left policies tend to favour limited state intervention in matters pertaining to the public interest.

In several countries, the terms far-left and radical left have been associated with many varieties of anarchism, autonomism and communism. They have been used to describe groups that advocate anti-capitalism and eco-terrorism. In France, a distinction is made between the centre-left and the left represented by the Socialist Party and the French Communist Party and the far-left as represented by anarcho-communists, Maoists and Trotskyists. The United States Department of Homeland Security defines "left-wing extremism" as groups that "seek to bring about change through violent revolution, rather than through established political processes". Similar to far-right politics, extremist far-left politics have motivated political violence, radicalisation, genocide, terrorism, sabotage and damage to property, the formation of militant organisations, political repression, conspiracism, xenophobia, and nationalism.

In China, the term Chinese New Left denotes those who oppose the economic reforms enacted by Deng Xiaoping in the 1980s and 1990s, favour instead the restoration of Maoist policies and the immediate transition to a socialist economy. In the Western world, the term New Left is used for social and cultural politics.

In the United Kingdom during the 1980s, the term hard left was applied to supporters of Tony Benn such as the Campaign Group and those involved in the London Labour Briefing newspaper as well as Trotskyist groups such as Militant and the Alliance for Workers' Liberty. In the same period, the term soft left was applied to supporters of the British Labour Party who were perceived to be more moderate and closer to the centre, accepting Keynesianism. Under the leadership of Tony Blair and Gordon Brown, the Labour Party adopted the Third Way and rebranded itself as New Labour in order to promote the notion that it was less left-wing than it had been in the past to accommodate the neoliberal trend arising since the 1970s with the displacement of Keynesianism and post-war social democracy. One of the first actions of Ed Miliband, the Labour Party leader who succeeded Blair and Brown, was the rejection of the New Labour label and a promise to abandon the Third Way and turn back to the left. However, Labour's voting record in the House of Commons from 2010 to 2015 indicated that the Labour Party under Miliband had maintained the same distance from the left as it did under Blair. In contrast, the election of Jeremy Corbyn as the Labour Party leader was viewed by scholars and political commentators as Labour turning back toward its more classical socialist roots, rejecting neoliberalism and the Third Way whilst supporting a democratic socialist society and an end to austerity measures.