John Locke (1632-1704)

Trained as physician and working as political advisor, Locke spent years exiled for opposing the Crown before writing philosophy that helped end divine-right monarchy. His anonymous 1689 Two Treatises of Government argued that legitimate authority requires governed consent - revolutionary doctrine with direct impact.

Jefferson's "life, liberty, and the pursuit of happiness" paraphrases Locke's "life, liberty, and property." Liberal democracy's foundational premise - that governments must respect individual rights - rests on Locke's articulation. His Essay Concerning Human Understanding argued that minds begin as blank slates, knowledge building from sensory experience rather than innate truths. This empiricist position challenged rationalist traditions and dominated epistemology for two centuries. He died in 1704, having reshaped Western understanding of both politics and mind.