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Brief Lives

Sir Karl Popper (1902-1994)

Alistair MacFarlane observes the logic of Karl Popper’s discoveries.

For centuries philosophers have sought to establish how knowledge can be securely founded. Karl Popper’s great insight was that a fundamental asymmetry between verification and falsification undermined this quest. No matter how often evidence is found to verify some theory, only one piece of sound contradictory evidence is sufficient to falsify it. This, in his view, killed Logical Positivism, which was based on an unworkable Principle of Verification.

Popper developed a philosophy of Critical Rationalism, which argued that security for knowledge can only lie in its ability to withstand new evidence and severe, sustained criticism.

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