Summa logicae

William of Ockham or Occam ( OK-əm; Latin: Guillelmus de Ockham; c. 1287 – 9/10 April 1347) was an English Franciscan friar, scholastic philosopher and theologian. He is considered to be one of the major figures of medieval thought and was at the centre of the major intellectual and political controversies of the 14th century. The nominalists of the fifteenth century regarded him as one of the founders of their movement. He is widely known for Occam's razor, the methodological principle that bears his name. He produced significant works on logic, physics and theology.