Task: Question Answering
Input (English): Passage: Despite his large number of works on Christian themes, Britten has sometimes been thought of as agnostic. Pears said that when they met in 1937 he was not sure whether or not Britten would have described himself as a Christian. In the 1960s Britten called himself a dedicated Christian, though sympathetic to the radical views propounded by the Bishop of Woolwich in Honest to God. Politically, Britten was on the left. He told Pears that he always voted either Liberal or Labour and could not imagine ever voting Conservative, but he was never a member of any party, except the Peace Pledge Union.Physically, Britten was never robust. He walked and swam regularly and kept himself as fit as he could, but Carpenter in his 1992 biography mentions 20 illnesses, a few of them minor but most fairly serious, suffered over the years by Britten before his final heart complaint developed. Emotionally, according to some commentators, Britten never completely grew up, retaining in his outlook something of a child's view of the world. He was not always confident that he was the genius others declared him to be, and though he was hypercritical of his own works, he was acutely, even aggressively sensitive to criticism from anybody else.Britten was, as he acknowledged, notorious for dumping friends and colleagues who either offended him or ceased to be of use – his "corpses". The conductor Sir Charles Mackerras believed that the term was invented by Lord Harewood. Both Mackerras and Harewood joined the list of corpses, the former for joking that the number of boys in Noye's Fludde must have been a delight to the composer, and the latter for an extramarital affair and subsequent divorce from Lady Harewood, which shocked the puritanical Britten. Among other corpses were his librettists Montagu Slater and Eric Crozier. The latter said in 1949, "He has sometimes told me, jokingly, that one day I would join the ranks of his 'corpses' and I have always recognized that any ordinary person must soon outlive his usefulness to such a great creative artist as Ben." Dame Janet Baker said in 1981, "I think he was quite entitled to take what he wanted from others ... He did not want to hurt anyone, but the task in hand was more important than anything or anybody." Matthews feels that this aspect of Britten has been exaggerated, and he observes that the composer sustained many deep friendships to the end of his life. 
Question: What is the name of the person that was a member of the Peace Pledge Union?
Output (English): Britten.