Published in 1899, *Reform or Revolution* was a direct challenge to Eduard Bernstein's 'revisionism,' which argued socialism could be achieved through gradual parliamentary reform. Luxemburg argued that while reforms are important for the working class's development, they cannot ultimately create a socialist society. She contended that capitalism is inherently unstable and will require a revolution to be overthrown, making this pamphlet a foundational text for the revolutionary socialist tradition.

In her 1913 economic masterwork, *The Accumulation of Capital*, Luxemburg argued that capitalism is inherently dependent on non-capitalist markets and social structures to survive. This need for constant expansion creates a dynamic of imperialism, colonialism, and war. She argued that capitalism's inevitable drive to consume these non-capitalist spheres would ultimately lead to its own collapse, as it destroys the very conditions on which it depends.

In her 1918 manuscript, written from prison, Luxemburg celebrated the Bolshevik seizure of power but sharply criticized their suppression of democratic freedoms. She argued that without a 'free struggle of opinions,' public institutions wither and socialism itself becomes a 'pseudo-vitality'. This critique flows directly from her belief that socialism and democracy are inseparable, a core principle that made her a critic of both reformist social democrats and authoritarian communists.

The phrase encapsulates Luxemburg's belief that the political and economic crises of capitalism presented humanity with a stark choice: a socialist revolution leading to a more just society, or a descent into chaos, war, and destruction. She saw the First World War as confirmation of capitalism's barbaric potential and argued that only through revolutionary struggle could the working class prevent this outcome and build a new world. This phrase has become a rallying cry for anti-capitalist movements ever since.

A common misconception is that Luxemburg was completely opposed to reforms. She did not reject reform out of hand, but believed it should be used to 'whet the appetite of the masses for more radical demands'. Her focus was on the necessity of a revolutionary transformation to achieve socialism, but she saw reforms as a crucial part of the struggle to develop working-class consciousness and improve material conditions in the short term. Her position was a strategic one, not a complete rejection of reformist work.