Centrism is the range of political ideologies that exist between left-wing politics and right-wing politics on the left–right political spectrum. It is associated with moderate politics, including people who strongly support moderate policies and people who are not strongly aligned with left-wing or right-wing policies. Centrism is commonly associated with liberalism, radical centrism, and agrarianism. Those who identify as centrist support gradual political change, often through a welfare state with moderate redistributive policies. Though its placement is widely accepted in political science, radical groups that oppose centrist ideologies may sometimes describe them as leftist or rightist.
Centrist parties in multi-party systems hold a strong position in forming coalition governments as they can accommodate both left-wing and right-wing parties, but they are often junior partners in these coalitions that are unable to enact their own policies. These parties are weaker in first-past-the-post voting and proportional representation systems. Parties and politicians have various incentives to move toward or away from the centre, depending on how they seek votes. Some populist parties take centrist positions, basing their political position on opposition to the government instead of left-wing or right-wing populism.
Centrism developed with the left–right political spectrum during the French Revolution, when assemblymen associated with neither the radicals nor the reactionaries sat between the two groups. Liberalism became the dominant centrist ideology in the 18th century with its support for anti-clericalism and individual rights, challenging both conservatism and socialism. Agrarianism briefly existed as a major European centrist movement in the late-19th and early-20th centuries. The eugenics associated with the Holocaust caused centrists to abandon scientific racism in favour of anti-racism. Centrism became more influential after the dissolution of the Soviet Union as it spread through Europe and the Americas, but it declined in favour of populism after the 2007–2008 financial crisis.
As with all ideological groups, the exact boundaries of what constitutes centrism are not perfectly defined, but its specific placement on the left–right political spectrum makes its position clearer relative to other ideologies. Centrism most commonly refers to a set of moderate political beliefs between left-wing politics and right-wing politics. Individuals who describe themselves as centrist may hold strong beliefs that align with moderate politics, or they may identify as centrist because they do not hold particularly strong left-wing or right-wing beliefs. In some cases, individuals who simultaneously hold strong left-wing beliefs and strong right-wing beliefs may also describe themselves as centrist. Although the left-centre-right trichotomy is well established in political science, individuals far from the political centre may occasionally reframe it, with the far-right alleging that the centre is leftist and the far-left alleging that the centre is rightist. Likewise, they may allege that their more moderate counterparts, the centre-left and the centre-right, are actually centrists because they are insufficiently radical.
Liberalism is commonly associated with the political centre. Both left-leaning and right-leaning variants of liberalism may be grouped within a broader understanding of centrism. In Europe, left-leaning liberalism emphasises social liberalism and is more common in nations with strong conservative movements, while right-leaning liberalism emphasises economic liberalism and is more common in nations with strong Christian democratic movements. Social liberalism combines centrist economic positions with progressive stances on social and cultural issues. Left-leaning liberalism generally sits closer to the centre than right-leaning liberalism.
Parties associated with social democracy and green politics commonly adopt the liberal position on social issues. Green parties, usually associated with left-wing politics, have a history of centrist economic policies in Central and Eastern Europe. Christian democracy, often considered a centre-right ideology, is sometimes grouped with the centre. Agrarianism may also be grouped with the centre. Agrarian parties are associated with the interests of farmers and other people associated with agriculture. Decentralization and environmental protection are also major agrarian ideals. These parties often developed in European countries where there was not a strong liberal movement, and vice versa, but they became less relevant by the mid-20th century.
Radical centrism is a form of centrism defined by its rejection of the left–right dichotomy or of ideology in general. Liberal scepticism and neo-republicanism can both be elements of radical centrism. Third Way politics is a radical centrist approach taken by centre-left parties to find a middle ground between capitalism and socialism. Though populism is commonly associated with strong left-wing or right-wing beliefs, centrist populism is critical of the political system independently of social, economic, and cultural issues. Centrist populist parties often do not have a strong ideological component, instead making anti-establishment politics the core of their message to capitalise on voter dissatisfaction and receive protest votes. These parties are most common in Central and Eastern Europe.
Centrism advocates gradual change within a political system, opposing the right's adherence to the status quo and the left's support for radical change. In contemporary politics, centrists generally support a liberal welfare state. Centrist coalitions are associated with larger welfare programs, but they are generally less inclusive than those organised under social democratic governments. Centrists may support some redistributive policies, but they oppose the total abolition of an upper class. Centrist liberalism seeks institutional reform, but it prioritises prudence when enacting change. European centrist parties are typically in favour of European integration and were the primary movers in the development of the European Union. Whether political positions are considered centrist can change over time. When radical positions become more widely accepted in society, they can become centrist positions.
Most political party systems lean toward the centre, with centre-left and centre-right parties compromising with centrist parties. Centrist parties hold a strong position in the formation of coalition governments, as they can accommodate both left-wing and right-wing parties, giving them additional leverage in the formation of a minority government. When radical parties become viable, forming a coalition with the centre can force them to moderate. Once in a coalition, the centrist party is typically a junior partner that has little ability to enact its own policy goals. Party systems with a strong centrist element are associated with lower interparty conflict. Centrist-controlled governments are much rarer than left-wing or right-wing governments. While approximately 30% of world leaders were centrist in the 1950s and 1960s, this declined to approximately 15% by 2020. Centrist dictatorships rarely occur.
In multi-party systems, the centre is challenged by parties that seek to undermine the legitimacy of the political system. These parties come from both the left and the right and have different positions on how the government should function, which prevents them from unifying against the centre, giving the centre an opportunity to retain power. According to the median voter theorem, parties are incentivised to move toward the political centre to maximise votes and to have the final say on closely-contested policies.
The overall effect of centrist parties on a political system is a subject of debate in political science, and it is not always clear whether they encourage or discourage political polarisation, or whether they benefit or suffer from it. One unanswered question in political philosophy is whether centrist parties create centripetal or centrifugal party systems. When centrist parties exert a centripetal force on other parties, it causes left-wing and right-wing parties to move closer to the centre and creates political stability. Alternatively, they may exert a centrifugal force in which left-wing and right-wing parties move away from the centre to pressure the centrist party into choosing a side, causing political instability.
Maurice Duverger argued that politics naturally drifts away from the centre into a two-party system and that a centrist party is an unnatural combination of the centre-left and centre-right. Giovanni Sartori argued that centrism is the default in a political system, but that the existence of a centrist party prevents the left and the right from moving toward the centre and encourages polarisation.
When parties become more extreme, disaffected moderates may be enticed to join centrist parties when they would otherwise have been unwilling to join an opposing party. More broadly, polarisation can lead to the fragmentation of the left and right into multiple parties, allowing a centrist party to perpetually be the Condorcet winner. Polarisation may also weaken a centrist party if both ends of a polarised society are made to oppose centrism.
Politicians with high approval might move to the centre to capitalise on their popularity with a larger voter base, while those seen as uncharismatic or incompetent may shift away from the centre to capture more reliable activist voters who will invest more into the politician's campaign. Relative to left-wing and right-wing parties, centrist parties are infrequently studied in political science.
Centrist parties face some intrinsic disadvantages when competing with left-wing and right-wing parties. Elections based on first-past-the-post voting or proportional representation provide less incentive for parties to hold centrist positions. Proportional representation systems weaken centrist parties because they incentivise the capture of specific voters instead of the general population. The popularity of centrism in the Western World is contradicted by the relative electoral weakness of centrist parties. One possible explanation for the paradox is that centrists may be perceived as lacking the leadership or capability demonstrated by leaders of other ideologies. Another is that centrists are unable to increase their vote share because the ideological space around them is already occupied by other parties.
In the Nordic countries where social democracy dominates politics, centrism competes with the centre-right to form a rightward flank. Centrist liberalism has only a minor presence in the Middle East, where it is overshadowed by leftism and Islamism. More developed countries in Latin America often have prominent centrist parties supported by the middle class. These have historically included the Radical Civic Union of Argentina, the Brazilian Democratic Movement, the Radical Party of Chile, and the Colorado Party of Uruguay. Christian democracy, usually a conservative movement, serves a similar role in Latin America as its opposition to more rightward politics moves it toward a centrist or centre-left position.
Centrism is part of the left–right political spectrum that developed during the French Revolution. When the National Assembly was organised, reactionary conservatives coalesced in the seats to the speaker's right, while the radicals sat on the speaker's left. The moderates who were not affiliated with either faction sat in the centre seats, and they came to be known as the centrists.
While liberalism began as a centre-left challenger to conservatism, it came to occupy the political centre of Western politics at the beginning of the 19th century as it also opposed radicalism and socialism. Liberal support for anti-clericalism and individual rights developed in opposition to conservatism, establishing the ideals that would accompany liberalism as it became the predominant centrist ideology in Europe. By the 1830s, conservatism and radicalism in Western Europe began a shift toward moderation as they accepted ideas associated with centrist liberalism. The United Kingdom was spared from the many revolutions during the early 19th century as its conservatives took a decisively centrist position, enlightened conservatism, and expressed willingness to compromise with the nation's strong radical element. As radicalism declined in Western Europe, liberalism and conservatism became the two dominant political movements.
Centrism in the United Kingdom was primarily supported by the Whigs and the middle class urbanites. The Bonapartism of Napoleon III brought French conservatism to the centre when it maintained an element of working class revolution. Empires were forced to maintain the political centre, avoiding reactionary or revolutionary politics that could have affected their stability. Centrist liberalism was slower to develop outside of the great powers of Western Europe. The United States saw a centrist liberal movement develop in the late-19th century through the Mugwumps of the Republican Party. The radical movement gave way to centrism after the 1870s as they both coalesced around ideals of republicanism, secularism, self-education, cooperation, land reform, and internationalism. Toward the end of the 19th century, agrarianism became a significant political movement in Europe to represent farmers' interests.
Western social science intertwined itself with centrism in the 19th century. As research universities became more common, advocacy for centrist reform was taken up by academics. Instead of engaging in direct activism, they considered social issues and presented their conclusions as objective science. Other ideological groups did not have success in this endeavour, as taking strong partisan stances risked one's reputation. Centrist liberals in Europe accepted scientific racism in the 19th century, but it did so less than its primary advocates, and it rejected the related concept of social Darwinism. Instead of the idea that non-white races could not achieve European-style civilisation, centrist liberals believed that they could but it would take them longer to do so.
Centrist liberalism was one of the two major global ideological groups at the beginning of the 20th century, where it was challenged by right-wing conservatism and Catholicism. Centrism faced increased pressure beginning in the interwar period as left-wing politics saw a resurgence, meaning centrism was challenged from both directions. Agrarianism lost much of its influence in the 1930s as nations fell under right-wing dictatorships, and its return in the 1940s was short-lived as nations fell under communist rule. The Nordic countries, which were mostly spared from both movements, were the only nations to retain strong agrarian parties. The Holocaust ended support for any scientific racism and eugenics espoused by centrist liberals, as they instead adopted antiracism as scientific truth. Following World War II, middle class centrist parties in developed countries became less common as they moved leftward or rightward.
Italy was dominated by the Christian Democracy party in the immediate aftermath of the war. Under the leadership of Alcide De Gasperi, it absorbed the centre-left and centre-right to create a centrist grouping and combat the Italian Communist Party. The group fractured during a leftward shift in the 1950s and 1960s as the leadership invited socialists into the party, hoping to deprive the Communist Party of an ally. Turkey developed a two-party system with two centrist parties in the 1950s. The parties were instead motivated by demographics: the Republican People's Party was supported by urban voters and the military while Democrat Party was the party of rural voters and businessmen. This system fell apart by the 1960s as polarisation grew and radical parties developed. Industrialisation reduced the appeal of agrarianism in the post-war era. The Agrarian Parties of Sweden, Norway, and Finland changed their names to the Centre Party in 1958, 1959, and 1965, respectively. This left Denmark as the only nation with a major self-proclaimed Agrarian Party, but it also described itself as liberal beginning in 1963.
Fiji implemented a political system designed to encourage centrism in an ethnically divided nation as it transitioned away from colonial rule in 1965. Each voter was to vote for four candidates, each for a distinct ethnic group. This failed to produce a centrist government, as in effect it solidified the ethnic division in government. As post-colonial party systems developed in the Middle East, the influence of one-party states varied. Parties like the Arab Socialist Union in Egypt and the General People's Congress in Yemen acted as restraints on political elites to keep them from deviating from the political centre. Anwar Sadat became president of Egypt, and in 1976 he split the ruling Arab Socialist Union into three parties based on its left, centre, and right factions. Rule was maintained through what became the centrist National Democratic Party, effectively controlling Egyptian politics and marginalising the other factions. The fall of dictatorships in countries such as Argentina, Chile, Peru, and Portugal in the 1980s was met by centrist parties that became the primary forces in transitioning the nations to democracy.
After the dissolution of the Soviet Union in the 1990s, centrist liberalism was seen as the dominant force in politics. The centre-left and the centre-right both moved closer to the centre in the 1990s and 2000s. The centre-right, previously dominated by neoliberalism, became more accepting of the welfare state, and it showed more support for combatting poverty and inequality. This included the "kinder, gentler America" championed by George H. W. Bush in the United States, Die Neue Mitte of Gerhard Schröder in Germany, the British "Thatcherism with a grey face" led by John Major, and the anti-neoliberalism of Mexican president Vicente Fox. The centre-left adopted Third Way policies, emphasising that it was neither left nor right but pragmatic. This adopted ideas popular among the centre-right, including balanced budgets and low taxes. Among these movements were British New Labour led by Tony Blair. Social democratic parties became more accepting of supply-side economics, austerity policies, and reduction of welfare programs. Some authoritarian powers, such as China and Russia, resisted the western liberal consensus.
In the Pacific, New Caledonia did not form a strong centrist movement until the 1990s as a consequence of the independence question. Conservative groups had actively suppressed centrist figures like Caledonian Union leader, who was accused of being a communist and prosecuted for allegedly organising the bombing of his own party newspaper's headquarters in the 1960s. Taiwan's political system, already inclined toward centrism, saw its two major parties move closer to the centrism in the late 1990s as newer parties developed on either side.
After a long period of strong left-wing and right-wing movements, Latin American nations trended toward centrism in the 2000s. This came about as the nations' economies strengthened and the reduction of wealth inequality created a larger middle class. Following the pink tide that saw several left-wing politicians take office, those in democratic nations adopted relatively moderate policies, including Luiz Inácio Lula da Silva in Brazil, Michelle Bachelet in Chile, Mauricio Funes in El Salvador, and Tabaré Vázquez and José Mujica in Uruguay. These nations implemented the Washington Consensus, which mixed deregulation and privatisation with the use of social programs. In many Latin American nations, opposing presidential candidates campaigned on similar platforms and often supported retaining their predecessors' policies without any significant changes, shifting the focus of elections to personality over ideology.
Support for centrism declined globally after the 2007–2008 financial crisis as it was challenged by populism and political polarisation. As of 2015, centrists made up a plurality in most European countries.