"The Necessity of Atheism" is a treatise on atheism by the English poet Percy Bysshe Shelley, printed in 1811 by C. and W. Phillips in Worthing while Shelley was a student at University College, Oxford. A copy of the first version was sent as a short tract signed enigmatically to all heads of Oxford colleges at the University. At that time the content was so shocking to the authorities that he was "rusticated" (expelled from the University) for refusing to deny authorship, together with his friend and fellow student, Thomas Jefferson Hogg. A revised and expanded version was printed in 1813.