René Descartes (1596–1650) was a French philosopher and mathematician. He is regarded as a foundational thinker in the development of Western ideas of reason and science. His philosophy was built on the idea of radical doubt, an understanding that nothing perceived or sensed is necessarily true. The only thing that can be true is doubting, or thinking, which is the essence of his famous phrase, “I think, therefore I am” (or, in Latin, “Cogito ergo sum”).
Plato (c. 428 BCE–c. 348 BCE) was an ancient Greek philosopher who wrote some of the most influential works in Western thought. A student of Socrates, Plato was so impressed by his teacher’s method of debate that he wrote all his works in the Socratic method of question-and-answer. Devastated after Socrates’ trial and death, Plato traveled for 12 years through Europe and Egypt studying mathematics, geometry, geology, astronomy and religion. During this period, Plato wrote his most famous works, including The Republic, which contains “The Allegory of the Cave.” On his return to Athens, Plato established the Academy—the first organized school in Western civilization.
Socrates (469–399 BCE) is the founding figure of Western philosophy. His style of teaching—immortalized as the “Socratic Method”—involved asking question after question until his students arrived at their own understanding. He wrote nothing himself, so the only record we have of his teachings comprises the writings of his followers, most notably Plato. After several acts of civil disobedience, Socrates was charged with failing to honor the Athenian gods and corrupting the young and was sentenced to death. Although colleagues begged him to escape, he chose to stay, spending his last days among friends before accepting the cup of hemlock from his executioner and drinking it.
Friedrich Nietzsche (1844–1900) lived on the tightrope between brilliance and madness. Largely ignored while he was alive, his insights about Western religion, music, morality and philosophy have affected generations of thinkers, psychologists, poets, novelists and playwrights. As one of his biographers wrote, “For Nietzsche, thinking was an act of extreme emotional intensity. He thought the way others feel.” Nietzsche wrote his masterpieces while suffering from bad health and terrible pain. In 1889, he collapsed, never to regain his mental health. He spent the last 11 years of his life deranged and eventually in silence. He died at age 66 in the care of his sister.
Georg Hegel (1770–1831) was a German philosopher and is considered to be the leading thinker of his era. His philosophies include the idea that progress is messy and nonlinear; ideas we disagree with hold kernels of truth we should examine; and growth requires the clash of different views, represented by the Dialectic: an accepted thesis, challenged by an opposing antithesis, resolving in a synthesis. At 48, he was appointed professor of philosophy at the University of Berlin.
Jim Collins (b. 1958) is teacher and writer dedicated to studying what makes great companies tick. He has written and co-authored eight books that have sold more than 10 million copies worldwide. His book, Good to Great, was a study of the success of unassuming, determined leaders who keep their focus on clear, simple goals—much like Jim himself.
Napoleon Hill (1883–1970) was an American self-help author. He was the first author to write about the connection between success and the powers of the mind, and his life’s work has become the cornerstone of modern motivation. Hill was born into poverty in the Appalachian town of Pound, in Southwest Virginia. At age 13, he began working as a mountain reporter on his father’s newspaper. He saved his earnings to enter law school, but had to withdraw due to a lack of money. He worked as a reporter until an assignment in 1908 changed the course of his life. While interviewing the powerful industrialist Andrew Carnegie, Carnegie challenged Hill to interview wealthy, successful men and see if he could discover the formula of their success. Published in 1937, Think and Grow Rich was an instant success and made Hill one of America’s most beloved motivational authors. It is still among the 10 best-selling self-help books and has never been out of print.