Danish thinker whose writings on faith, choice and individuality helped shape existential philosophy.

Ancient Greek thinker whose work profoundly influenced philosophy, science, logic, ethics and political thought.

Historian and public intellectual whose work ranged across world history, international affairs, religion and contemporary politics.

Third US president and principal author of the Declaration of Independence, central to the early republic.

Writer and philosopher who linked science, history and spirituality while influencing modern consciousness movements.

Anglican dean, theologian and writer known for Christian Platonism, mysticism and cultural commentary.

Novelist and philosopher who developed Objectivism and wrote influential works including Atlas Shrugged.