Section 1: Warm Up Lead Background Information About the author Bertrand russell: a british philosopher and political activist Russell became the best-known philosopher of his time because of the volume and clarity of his writing, and the vigor and prominence of his political activism. His major early work was The Principles 0 Mathematics, first published in 1903 1872-1970Section 1: Warm Up About the Author Bertrand Russell: a British philosopher and political activist. Russell became the best-known philosopher of his time because of the volume and clarity of his writing, and the vigor and prominence of his political activism. His major early work was The Principles of Mathematics, first published in 1903. 1872-1970 Lead-in Background Information