Karl Popper (1902–1994) defended liberal democracy, critical rationalism, and piecemeal social engineering in The Open Society and Its Enemies (1945). Key points:
- Open society vs. closed society: Open societies permit critical debate, individual freedom, and change; closed societies rest on tribal, mystical, or historicist dogmas that suppress criticism.
- Critique of historicism: Popper rejects the idea that history follows inexorable laws or predictable destinies (Hegel, Marx). He argues that social science should not try to predict large historical outcomes; instead, we should use trial-and-error methods.
- Fallibilism and critical rationalism: Knowledge is always provisional. Scientific and social progress occur through conjectures and refutations—criticize, test, and discard bad ideas rather than seek certain foundations.
- Piecemeal social engineering: Instead of radical utopian redesigns, improve institutions incrementally, correcting identifiable harms while minimizing risks of authoritarianism.
- Political implications: Support for individual rights, pluralism, democratic institutions, and opposition to totalitarianism. Popper links closed thinking and historicist determinism to justification for tyranny.
Key sources:
- Karl Popper, The Open Society and Its Enemies (1945).
- Karl Popper, The Logic of Scientific Discovery (1934) — for his epistemology.
- Bryan Magee, The Philosophy of Karl Popper (1973) — accessible overview.