The socialist commitment to equality (egalitarianism) is the core feature of socialism and is what makes it very different from the other two main ideologies (liberalism and conservatism). This belief focuses not just on equality of opportunity or legal equality, but on social equality- equality of outcome. They believe in this for three main reasons;

Socialists believe in equality as a fundamental political principle and a key aspect of human nature. The core belief in socialism is equality of outcome, which surpasses liberal notions of equal rights and opportunities. Socialists argue that capitalism has led to significant inequality by promoting competition and exploitation. They point to inherited financial and status-related privileges as perpetuating this disparity. Socialists assert that societal structures, not individual skills and talents, are the primary drivers of inequality. True social equality, they argue, will enable individuals to reach their full potential without constraints like debt or poor health. There is a discussion within socialism about the interpretation of equality of outcome: should the focus be on narrowing or eliminating the wealth gap? Different socialist factions propose distinct economic systems to address these disparities. Some advocate for the abolition of capitalism in favor of common ownership, while others, like social democrats, suggest using the welfare state to reduce inequality through measures like progressive taxation. Supporters of the "third way" approach, on the other hand, prioritize reducing social exclusion and poverty through initiatives like tax credits and minimum wage adjustments, without emphasizing complete equality of outcome.

Socialist egalitarianism is characterized by a belief in social equality, or equality of outcome. Socialists have advanced at least three arguments in favour of this form of equality. 

First, social equality upholds justice or fairness. Socialists are reluctant to explain the inequality of wealth simply in terms of innate differences of ability among individuals. Socialists believe that just as capitalism has fostered competitive and selfish behaviour, human inequality very largely reflects the unequal structure of society. They do not hold the naïve belief that all people are born identical, possessing precisely the same capacities and skills.

An egalitarian society would not, for instance, be one in which all students gained the same mark in their mathematics examinations. Nevertheless, socialists believe that the most significant forms of human inequality are a result of unequal treatment by society, rather than unequal endowment by nature.

Justice, from a socialist perspective, therefore demands that people are treated equally (or at least more equally) by society in terms of their rewards and material circumstances. Formal equality, in its legal and political senses, is clearly inadequate in itself because it disregards the structural inequalities of the capitalist system. Equality of opportunity, for its part, legitimizes inequality by perpetuating the myth of innate inequality.

Second, social equality underpins community and cooperation. If people live in equal social circumstances, they will be more likely to identify with one another and work together for common benefit. Equal outcomes therefore strengthen social solidarity. Social inequality, by the same token, leads to conflict and instability. This also explains why socialists have criticized equality of opportunity for breeding a ‘survival of the fittest’ mentality. R. H. Tawney  for example, dismissed the idea of equal opportunities as a ‘tadpole

philosophy’, emphasizing the tiny proportion of tadpoles that develop into frogs. 

Third, socialists support social equality because they hold that need-satisfaction is the basis for human fulfilment and self-realization. A ‘need’ is a necessity: it demands satisfaction; it is not simply a frivolous wish or a passing fancy. Basic needs, such as the need for food, water, shelter, companionship and so on, are fundamental to the human condition, which means that, for socialists, their satisfaction is the very stuff of freedom. Marx expressed this in his communist theory of distribution: ‘From each according to his ability, to each according to his needs.’ Since all people have broadly similar needs, distributing wealth on the basis of need-satisfaction clearly has egalitarian implications. Nevertheless, need-satisfaction can also have inegalitarian implications, as in the case of so-called ‘special’ needs, arising, for instance, from physical or mental disability.

While socialists agree about the virtue of social and economic equality, they disagree about the extent to which this can and should be brought about. Marxists and communists believe in absolute social equality, brought about by the abolition of private property and collectivization of productive wealth.

Perhaps the most famous experiment in such radical egalitarianism took place in China under the ‘Cultural Revolution’  Social democrats, however, believe in relative social equality, achieved by the redistribution of wealth through the welfare state and a system of progressive taxation. The social- democratic desire to tame capitalism rather than abolish it, reflects an acceptance of a continuing role for material incentives, and the fact that the significance of need-satisfaction is largely confined to the eradication of poverty. This, in turn, blurs the distinction between social equality and equality of opportunity