Sir Karl Raimund Popper (1902-1994), the author of Conjectures and Refutations, was an Austrian-British philosopher of science. He is best known for his defense of critical rationalism and empirical falsification as the basis of the scientific method. Beyond philosophy, Popper is also remembered for his contributions as a social commentator, most prominently for his defense of liberal democracy.

Popper was born in Vienna to a family of well-connected scholars. He attended the University of Vienna, where he furthered his interest in mathematics, philosophy, psychology, and physics. As a student, Popper became interested in Marxism and joined the Social Democratic Workers’ Party of Austria. However, after growing disillusioned with Marx’s defense of historicism, Popper later became a proponent of social liberalism. He earned a PhD in Philosophy in 1928, and would later hold teaching posts at Canterbury University College in New Zealand and the London School of Economics.

Popper’s most famous work, Conjectures and Refutations, remains one of the most influential publications on critical rationalism. It is the strongest argument against the inductivist view of the scientific method, which believes that new scientific theories are inferred from observing previously-known cases.