Baruch Spinoza had a monumental impact on Enlightenment thought. His rationalist philosophy emphasized the role of logic and reason in understanding the universe and society. Spinoza's ideas on freedom of thought, religious tolerance, and ethical living challenged traditional doctrines, advocating a more secular and humanistic worldview. His writings, particularly on ethics and metaphysics, influenced later thinkers, contributing to the development of modern philosophy and the clarification of individual rights and freedoms.