Letters on the English author of "Novum Organum" and father of experimental philosophy. Letter 13 is about John Locke and his theories on the immortality of the soul. Letter 14 compares British philosopher Isaac Newton to French philosopher René Descartes. Upon his death in 1727, Newton was compared to Descartes in a eulogy performed by French philosopher Fontenelle. While the British did not appreciate this comparison, Voltaire argues that Descartes, too, was a great philosopher and mathematician. Letter 15 focuses on Newton's law of universal gravitation. Letter 16 talks about Newton's work with optics. Letter 17 discusses Newton's work with geometry and his theories
Philosophy of Søren Kierkegaard Philosophy of Søren Kierkegaard The philosophy of Søren Kierkegaard has been a major influence in the development of 20th-century philosophy, especially existentialism and postmodernism. Kierkegaard was a 19th-century Danish philosopher who has been labeled by many as the "Father of Existentialism", although there are some in the field who express doubt in labeling him an existentialist to begin with. His philosophy also influenced the development of existential psychology. Kierkegaard criticized aspects of the philosophical systems that were brought on by philosophers such as Georg Wilhelm Friedrich Hegel before him and the Danish Hegelians. He was also indirectly influenced by the