George Bernard Shaw (26 July 1856 - 2 November 1950), known at his insistence simply as Bernard Shaw, was an Irish playwright, critic, polemicist, and political activist. His influence on Western theatre, culture and politics extended from the 1880s to his death and beyond. He wrote more than sixty plays, including major works such as Man and Superman (1902), Pygmalion (1912) and Saint Joan (1923). With a range incorporating both contemporary satire and historical allegory, Shaw became the leading dramatist of his generation, and in 1925 was awarded the Nobel Prize in Literature.

Shaw was born at 3 Upper Synge Street in Portobello, a lower-middle-class part of Dublin. He was the youngest child and only son of George Carr Shaw (1814-1885) and Lucinda Elizabeth (Bessie) Shaw (nee Gurly; 1830-1913). His elder siblings were Lucinda (Lucy) Frances (1853-1920) and Elinor Agnes (1855-1876). The Shaw family was of English descent and belonged to the dominant Protestant Ascendancy in Ireland; George Carr Shaw, an ineffectual alcoholic, was among the family's less successful members. His relatives secured him a sinecure in the civil service, from which he was pensioned off in the early 1850s; thereafter he worked irregularly as a corn merchant. In 1852 he married Bessie Gurly; in the view of Shaw's biographer Michael Holroyd she married to escape a tyrannical great-aunt. If, as Holroyd and others surmise, George's motives were mercenary, then he was disappointed, as Bessie brought him little of her family's money. She came to despise her ineffectual and often drunken husband, with whom she shared what their son later described as a life of "shabby-genteel poverty".  By the time of Shaw's birth, his mother had become close to George John Lee, a flamboyant figure well known in Dublin's musical circles. Shaw retained a lifelong obsession that Lee might have been his biological father; there is no consensus among Shavian scholars on the likelihood of this. The young Shaw suffered no harshness from his mother, but he later recalled that her indifference and lack of affection hurt him deeply. He found solace in the music that abounded in the house. Lee was a conductor and teacher of singing; Bessie had a fine mezzo-soprano voice and was much influenced by Lee's unorthodox method of vocal production. The Shaws' house was often filled with music, with frequent gatherings of singers and players.  In 1862, Lee and the Shaws agreed to share a house, No. 1 Hatch Street, in an affluent part of Dublin, and a country cottage on Dalkey Hill, overlooking Killiney Bay. Shaw, a sensitive boy, found the less salubrious parts of Dublin shocking and distressing, and was happier at the cottage. Lee's students often gave him books, which the young Shaw read avidly; thus, as well as gaining a thorough musical knowledge of choral and operatic works, he became familiar with a wide spectrum of literature.  Between 1865 and 1871, Shaw attended four schools, all of which he hated. His experiences as a schoolboy left him disillusioned with formal education: "Schools and schoolmasters", he later wrote, were "prisons and turnkeys in which children are kept to prevent them disturbing and chaperoning their parents." In October 1871 he left school to become a junior clerk in a Dublin firm of land agents, where he worked hard, and quickly rose to become head cashier. During this period, Shaw was known as "George Shaw"; after 1876, he dropped the "George" and styled himself "Bernard Shaw".  In June 1873, Lee left Dublin for London and never returned. A fortnight later, Bessie followed him; the two girls joined her. Shaw's explanation of why his mother followed Lee was that without the latter's financial contribution the joint household had to be broken up. Left in Dublin with his father, Shaw compensated for the absence of music in the house by teaching himself to play the piano.

Using a quote from the above article, answer the following question: what did he do when he finished school?
In October 1871 he left school to become a junior clerk in a Dublin firm of land agents, where he worked hard, and quickly rose to become head cashier.