Einstein: The German-American physicist Albert Einstein contributed more than any other scientist to the 20th-century vision of physical reality. In the wake of World War I, Einstein's theories, especially his theory of relativity, seemed to many people to point to a "pure quality of human thought," one far removed from the war and its aftermath. The "Theory of Relativity" to some extent concerns the influence and importance of your "frame of reference" when posing and answering a question.

Aristotle: With the possible exception of Plato, Aristotle, 384-322 BC, is the most influential philosopher in the history of Western thought. Logic into the present century was basically Aristotelian logic. He valued the importance of "actualizing" your "potential." The substance of something, according to Aristotle, is a merging of matter into form. The term "matter" is used by Aristotle in four overlapping senses. First, it is the underlying structure of changes, particularly changes of growth and of decay. Secondly, it is the potential which has implicitly the capacity to develop into reality. Thirdly, it is a kind of stuff without specific qualities and so is indeterminate and contingent. Fourthly, it is identical with form when it takes on a form in its actualized and final phase.The study of the natural sciences was dominated by Aristotle until early modern times, and modern physics was developed in reaction to the Aristotelian tradition. His metaphysics continues to be the subject of philosophical debate, although his ethics now constitutes that part of his philosophy which appeals most to contemporary philosophers. Aristotle's influence extends far beyond philosophy, however. For example, Aristotle was the founder of biology; Charles Darwin regarded him as the most important contributor to the subject.

Plato: Greek philosopher - 427-347 B.C. Note: Dates are approximate, there is some uncertainty as to his birth and death. Plato was a student of Socrates until the latter's death in 399 BC at the hands of the Athenian authorities. After his teacher's death, Plato traveled extensively, including journeys in Egypt. He believed that all things should be done for "the greater good," rather than to let personal agendas override the importance of what is best for the majority. In 387 BC he returned to Athens and founded the Academy, a school of science and philosophy, that became the model for the modern university. Perhaps the most famous student of the Academy was Aristotle whose teachings have had tremendous impact on philosophy through today. Due to the Academy's safekeeping, many of Plato's works have survived. His extant writings are in the form of letters and dialogues, the most famous of which is probably The Republic. His writings cover subjects ranging from knowledge to happiness to politics to nature.

Karl (Heinrich)Marx: (1818-83) Founder of international Communism, born in Trier, Germany. He studied law at Bonn and Berlin, but took up history, Hegelian philosophy, and Feuerbach's materialism. He edited a radical newspaper, and after it was suppressed he moved to Paris (1843) and Brussels (1845). There, with Engels as his closest collaborator and disciple, he reorganized the Communist League, which met in London in 1847. In 1848 he finalized the Communist Manifesto, which attacked the state as the instrument of oppression, and religion and culture as ideologies of the capitalist class. He was expelled from Brussels, and in 1849 settled in London, where he studied economics, and wrote the first volume of his major work, Das Kapital (1867, two further volumes were added in 1884 and 1894). He was a leading figure in the First International from 1864 until its demise in 1872. The last decade of his life was marked by increasing ill health. He is buried in Highgate Cemetery, London. Marx believed strongly in the impact of thoughts and ideas (historical influences) on the development of society. Historical materialism is a line of thought that emphasizes the importance of societal structures rather than economic and political theory for the political and economic development of a society.

Niccolò Machiavelli: (1469-1527) Early in the fifteenth century, Niccolò Machiavelli began his career as an active politician and diplomat in the independent city-state of Florence. After more than a decade of public service, he was driven from his post when the republic collapsed. Repeated efforts to win the confidence and approval of the new regime were unsuccessful, and Machiavelli was forced into retirement and a life of scholarship about the political process instead of participation in it. The books for which he is remembered were published only after his death. Machiavelli originally wrote Il Principe (The Prince) in 1513 in hopes of securing the favor of the ruling Medici family. It is an intensely practical guide to the exercise of raw political power over a renaissance principality. Allowing for the unpredictable influence of fortune, Machiavelli argued that it is primarily the character or virtue or skill of the individual leader that determines the success of a state. The book surveys various bold means of acquiring and maintaining the principality and evaluates each of them solely by reference to its likelihood of augmenting the glory of the prince. It is this focus on practical success by any means, even at the expense of traditional moral values, that earned Machiavelli a reputation for ruthlessness, deception, and cruelty, but some feel his philosophies were misinterpreted in that light.

Hippocrates: (c.460-377 BC) Hippocrates was a physician, and in fact is known as "the father of medicine." He is also associated with the medical profession's "Hippocratic oath." Born on the island of Cos, Greece, he is considered to be the most celebrated physician of antiquity. He gathered together all that was sound in the previous history of medicine. A collection of 70 works, the Hippocratic corpus, has been ascribed to him, but very few were written by him. It is more likely that they formed a library at a medical school.

Jung: "Jungian" psychology takes its name from Carl Gustav Jung, 1905-1961, madman by some accounts, psychological genius by others. Jung spent his life exploring an idea first "discovered" by Sigmund Freud: The idea that human behavior, emotion, thought, and experience are all greatly influenced by psychological forces beyond the control or awareness of human consciousness. Jung took this notion one step further, however, and suggested that these "forces" were archetypically governed, and that archetypes were independent agents with their own motivations and agendas. These archetypes appear in various guises in all cultures, times, and places, and their stories find expression through mythology.

Sartre: Jean-Paul Sartre (1905-1980)... Sartre was born on June 21, 1905, in Paris. Having lost his father at an early age, Sartre was raised by his grandfather, Carl Schweitzer, who was the uncle of the famous medical missionary, Albert Schweitzer. Sartre was an awkward child, small and cross-eyed, not easily accepted by other children. In response to this unsettled and unhappy childhood, the young Sartre immersed himself in reading and writing. Sartre taught in Le Havre, Leon, and Paris. He adopted the phenomenological method, which endorses careful description of consciousness as the philosophical starting point, as opposed to metaphysical deductions and presuppositions which he thought had nothing to do with experience. Sartre was disillusioned with conventional philosophy, which he felt could not address the concrete experiences and free choices of life. Sartre believed that there are no predetermined values, ethical or otherwise. In 1939 he was drafted to fight for the French against the invading Germans. He was captured by the Germans in 1940 and released in 1941 because of poor health. He proceeded to work in the French Resistance movement. Sartre showed concern for the poor and oppressed, and in his work after the War he attempted to communicate a need for social responsibility. His later writings and teachings put across the concept that humans are free from the deterministic realm of things and are completely responsible for all their actions. He remained active in political movements until the 70's, when he became blind and his health deteriorated. He died in April of 1980 of a lung tumor.

Ludwig Joseph Johann Wittgenstein : {vit'-gen-shtyn}(1889-1951) As for his career, Wittgenstein studied mechanical engineering in Berlin and in 1908 went to Manchester, England to do research in aeronautics, experimenting with kites. His interest in engineering led to an interest in mathematics which in turn got him thinking about philosophical questions about the foundations of mathematics. He visited the mathematician and philosopher Gottlob Frege (1848-1925), who recommended that he study with Bertrand Russell (1872-1970) in Cambridge. At Cambridge Wittgenstein greatly impressed Russell and G.E. Moore (1873- 1958), and began work on logic. When his father died in 1913 Wittgenstein inherited a fortune, which he quickly gave away.

When war broke out the next year, he volunteered for the Austrian army. He continued his philosophical work and won several medals for bravery during the war. The result of his thinking on logic was the Tractatus Logico-Philosophicus which was eventually published in 1922 with Russell's help. This was the only book Wittgenstein published during his lifetime. Here and elsewhere in the Tractatus Wittgenstein seems to be saying that the essence of the world and of life is: This is how things are. One is tempted to add "--deal with it." Having thus, in his opinion, solved all the problems of philosophy, Wittgenstein became an elementary school teacher in rural Austria, where his approach was strict and unpopular, but apparently effective. In 1929 he returned to Cambridge to teach at Trinity College, recognizing that in fact he had more work to do in philosophy. He became a naturalized British subject in 1938. He became professor of philosophy at Cambridge in 1939. During World War II he worked as a hospital porter in London and as a research technician in Newcastle. After the war he returned to university teaching but resigned his professorship in 1947 to concentrate on writing. Much of this he did in Ireland, preferring isolated rural places for his work. By 1949 he had written all the material that was published after his death as Philosophical Investigations, arguably his most important work. He spent the last two years of his life in Vienna, Oxford and Cambridge and kept working until he died of prostate cancer in Cambridge in April 1951. His work from these last years has been published as On Certainty. His last words were, "Tell them I've had a wonderful life." Philosopher, born in Vienna.

Charles Darwin: British Naturalist, 1809 -1882 A.D. Charles Darwin was born on February 12, 1809 in Shrewsbury, England. He was the British naturalist who became famous for his theories of evolution. Like several scientists before him, Darwin believed all the life on earth evolved (developed gradually) over millions of years from a few common ancestors. From 1831 to 1836 Darwin served as naturalist aboard the H.M.S. Beagle on a British science expedition around the world. Darwin studied plants and animals everywhere he went, collecting specimens for further study. Upon his return to London Darwin conducted thorough research of his notes and specimens. Out of this study grew several related theories: one, evolution did occur; two, evolutionary change was gradual, requiring thousands to millions of years; three, the primary mechanism for evolution was a process called natural selection; and four, the millions of species alive today arose from a single original life form through a branching process called "specialization." He set these theories forth in his book called, "On the Origin of the Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life" (1859) or "The Origin of the Species" for short. Darwin's work had a tremendous impact on religious thought. Many people strongly opposed the idea of evolution because it conflicted with their religious convictions. Darwin avoided talking about the theological and sociological aspects of his work, but other writers used his theories to support their own theories about society.

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