New College Library holds this copy of William of Ockham’s  De Sacramento Altaris,  a treatise on the Eucharist, in the Incunabula collection.

William of Ockham was born at Ockham, near Guildford in Surrey in 1287 and he died on the night of April 9 1347 in Munich. The future theologian and  philosopher entered the Franciscan order before the age of fourteen. He was educated at the Franciscan convent in London, and developed an academic career as a  lecturer and theological writer in Oxford and London. His unconventional views attracted attention within the Church and in1324 Ockham was apparently summoned to Avignon to have his writings examined for heresy, but in the end no formal condemnation took place. However his life came to a crisis after he challenged the doctrine of  Pope John XXII, saying that Jesus and the apostles owned no property but,  like the Franciscans,  lived by begging and the generosity of others. Along with other Franciscans he fled to Munich where he ended his days.

The methodological principle known as “Ockham’s Razor” states that among competing hypotheses, the one that makes the fewest assumptions should be selected. It is described as a razor because it distinguishes between hypotheses by “shaving away” unnecessary assumptions.

Sources:

(1) Spade, Paul Vincent and Panaccio, Claude, “William of Ockham”, The Stanford Encyclopedia of Philosophy (Fall 2011 Edition), Edward N. Zalta (ed.), URL = <http://plato.stanford.edu/archives/fall2011/entries/ockham/>.

(2) W. J. Courtenay, ‘Ockham, William (c.1287–1347)’, Oxford Dictionary of National Biography, Oxford University Press, 2004; online edn, May 2010 [http://www.oxforddnb.com/view/article/20493, accessed 8 April 2013]