Socialism

#### Definition
Socialism is a philosophy for social ownership of production to achieve equality.

#### Core Principles
- Social ownership, equality, production for use.

#### Historical Origins and Development
From Enlightenment; industrialized in 19th century.

#### Key Thinkers or Figures
- Karl Marx, Henri de Saint-Simon.

#### Notable Variants
- Utopian, scientific, democratic, market.

#### Criticisms or Controversies
Association with authoritarianism, economic failures.