Socrates - Known for his Socratic method, he emphasized self-examination and questioning. His ideas laid the foundation for Western philosophy.
Aristotle - A polymath, Aristotle's contributions to logic, metaphysics, ethics, and more are fundamental to Western philosophy and science.
Plato - Founder of the Academy in Athens, Plato's theory of forms and his work 'The Republic' continue to influence philosophical thought.
Descartes - René Descartes is known for his phrase 'I think, therefore I am' and his dualism of mind and body, shaping modern philosophy.
Kant - Immanuel Kant's 'Critique of Pure Reason' revolutionized metaphysics and epistemology, introducing the concept of the 'categorical imperative'.
Nietzsche - Friedrich Nietzsche's ideas on morality, the 'will to power', and the 'Ubermensch' challenged traditional values and influenced existentialism.