A rare 300-year-old letter written by one of history's most renowned philosophers was recently presented to University Library System (ULS) Director Rush Miller (on left) by Nicholas Rescher, Distinguished University Professor of Philosophy at Pitt and cochair of Pitt's Center for Philosophy of Science. The three-page letter, written in 1711, is the highlight of Rescher's massive collection of materials on philosophy he began donating to ULS last year. The letter was written by theologian Michael Gottlieb Hansch (1683-1749) to G.W. Leibnitz (1646-1716), the celebrated philosopher and mathematician who was an inventor of and contributor to calculus. Hansch was a biographer of German astronomer and astrologer Johannes Kepler (1571-1630). In the letter, Leibnitz asked several questions about Kepler's writings, but also touched upon other, theological matters, including divine justice, infant sin, and freedom of the will. A fourth page of the letter was left blank for Leibnitz's response. Leitnitz wrote back to Hansch, answering his questions and encouraging him to move ahead with publishing Kepler's manuscripts. The rare letter is now housed along with Rescher's other papers in Pitt's Archives of Scientific Philosophy. Rescher, who chaired the philosophy department at Pitt in 1980-81, has authored more than 100 books and hundreds of journal articles on many areas of philosophy.