Despite his early promise, Moore's parents had been against him training as a sculptor, a vocation they considered manual labour with few career prospects. After a brief introduction as a student teacher, Moore became a teacher at the school he had attended. Upon turning eighteen, Moore volunteered for army service in the First World War. He was the youngest man in the Prince of Wales' Own Civil Service Rifles regiment and was injured in 1917 in a gas attack, on 30 November at Bourlon Wood, during the Battle of Cambrai. After recovering in hospital, he saw out the remainder of the war as a physical training instructor, only returning to France as the Armistice was signed. He recalled later, "for me the war passed in a romantic haze of trying to be a hero." This attitude changed as he reflected on the destructiveness of war and in 1940 he wrote, in a letter to his friend Arthur Sale, that "a year or two after [the war] the sight of a khaki uniform began to mean everything in life that was wrong and wasteful and "anti-life". And I still have that feeling."