Murray Gell-Mann is one of the leading physicists of the world. He was awarded the Nobel Prize in Physics in 1969 for his work on the classification and symmetries of elementary particles, including the approximate SU(3) symmetry of hadrons. His list of publications is impressive; a number of his papers have become landmarks in physics. In 1953, Gell-Mann introduced the strangeness quantum number, conserved by the strong and electromagnetic interactions but not by the weak interaction. In 1954 he and F E Low proposed what was later called the renormalization group. In 1958 he and R P Feynman w