Although he was best known for his contributions to logic and philosophy, Bertrand Russell’s range of interests was impressively wide. He was engaged in what seemed to be the entire extent of human endeavor: not only was he deeply involved with mathematics, philosophy, science, and logic, but he was also interested in political activism, social justice, education, and sexual morality. His influence has been so pervasive that in some ways it has become difficult for us to appreciate its full impact. Russell’s work has fundamentally changed the way philosophy is practiced and the way we understand logic, mathematics, and science.

Bertrand Arthur William Russell was born into a privileged English family on May 18, 1872. He was the grandson of Lord John Russell, who was the first Earl of Russell as well as a former prime minister. Bertrand’s early life was traumatic: orphaned by the age of four, he and his elder brother Frank were sent to live with their strict grandparents. Lord Russell died when Bertrand was six, and thereafter the boys were raised by their austerely religious, authoritarian grandmother. Russell’s youth was filled with rules and prohibitions, and his earliest desire was to free himself from such constraints. His lifelong distrust of religion no doubt stems from this early experience. As was customary for children of his social class, Russell was initially tutored at home. Later, he attended Trinity College, Cambridge, where he achieved first-class honors in mathematics and philosophy. At Cambridge, under the tutelage of the Hegelian philosopher J.M.E. McTaggart, Russell became a proponent of idealism, the belief that all reality is ultimately a product of the mind. Some years after graduating, however, Russell and his colleague G.E. Moore came to reject idealism in favor of realism, the belief that the external world exists independently of experience and consciousness. Russell became part of a general revitalization of empiricism, the belief that all human knowledge is derived from our sensory experience of the external world. By the time Russell published the philosophical works discussed here (The Problems of Philosophy and Our Knowledge of the External World), he was working firmly in the empiricist tradition.

Russell graduated from Cambridge in 1894 and was briefly an attaché at the British Embassy in Paris. In 1895, he returned to England, where he became a fellow of Trinity College and married his first wife, Alys Pearsall Smith. A year later, after a visit to Berlin, he published German Social Democracy, the first of his seventy-odd books.

Russell’s important early work was concerned with mathematics. Russell’s great contribution to logic and mathematics was his defense of logicism—that is, the theory that all mathematics can, in some fundamental way, be reduced to logical principles. The logicist project was important because, if it could be achieved, then mathematics would be established as a field of certain knowledge and not one of conjecture. Mathematics could legitimately be considered a priori knowledge, meaning knowledge that is necessary and self-evident, completely objective, and independent of human experience. The search for legitimately a priori knowledge has been a major occupation of philosophy throughout history. Over the course of his career, Russell remained preoccupied with the questions of what we can know with absolute certainty and how we can know it. The Principia Mathematica, Russell’s three-volume treatise on logicism, coauthored with A. N. Whitehead, is full of painstaking proofs that attempt to establish that numbers, arithmetic, and all mathematical principles can be derived from formal logic. This dedication to rigor and interest in justification is a recurring characteristic in Russell’s work.

Along with G. E. Moore and with Russell’s student Ludwig Wittgenstein, Russell is considered one of the founding proponents of analytic philosophy. Analytic philosophy describes both a historical tradition (the tradition following Moore and Russell) and a general approach to the practice of philosophy. Analytic philosophy—which has come to be virtually synonymous with “logical positivism”—refers to a belief that philosophy should be executed with the same rigor and precision as scientific inquiry. Analytic philosophy is characterized by a skeptical distrust of assumptions and a methodical system of analysis based on logic. Just as he used logic to describe the foundations of mathematics in Principia Mathematica, Russell would use logic to clarify philosophy, through his concept of logical atomism, and linguistics, through his theory of descriptions. Although the subject matter differed across his career, Russell’s analytic methodology remained more or less constant. Many of the particulars of Russell’s analysis have been challenged or refuted, but his legacy as an analyst remains undeniably influential.

Although Russell’s intellectual reputation is based on his work as a mathematician, philosopher, and logician, Russell was also noted for his work as a social reformer. In fact, he first became known to the general public because of his political and social work rather than his publications. When the First World War broke out, Russell publicly voiced increasingly controversial political views. He became an activist for pacifism, which resulted in his dismissal from Trinity College in 1916. Two years later, his opposition to British involvement in the war landed him in prison. Stripped of his teaching job, he began to make his living by writing and lecturing independently. In 1919, Russell visited the newly formed Soviet Union, where he met many of the famous personalities of the revolution he had initially supported. The visit soured his view of the Socialist movement in Russia, and later that year he wrote a scathing attack titled Theory and Practice of Bolshevism. In 1921, he married his second wife, Dora Black, with whom he explored his interest in education. Russell and Black opened the progressive Beacon Hill School, and Russell wrote such works as On Education (1926) and, a few years later, Education and the Social Order (1932).

In 1931, Russell became the third Earl of Russell. Five years later, he divorced Dora Black and married his third wife, Patricia Spence. By this time, he was extremely interested in morality and had written on the subject in his controversial book Marriage and Morals (1932). He had moved to New York to teach at City College but was dismissed from the position because of his unconventional, liberal attitudes on sexuality. When Adolf Hitler came to power in Germany, Russell began to question his own dogmatic pacifism and by 1939 had rejected it in favor of a more relativist position. Believing Nazism to be an evil that needed to be stopped at all costs, he campaigned tirelessly against it throughout the Second World War. He returned to England from the United States in 1944. His teaching position at Trinity College was restored to him, and he was granted the Order of Merit by King George VI. In the period that followed, he wrote several important books, including An Enquiry into Meaning and Truth (1940), Human Knowledge: Its Scopes and Limits (1948), and his best-known work from the period, History of Western Philosophy (1945). He also continued writing controversial pieces on social, moral, and religious issues. Most of these were collected and published in 1957 as Why I Am Not a Christian. From 1949 and for the rest of his life, he was an active advocate of nuclear disarmament. In 1950, Russell won the Nobel Prize in Literature. He spent his final years in North Wales, actively writing until the end. He died on February 2, 1970.