Sigmund Freud was a world-famous doctor of Vienna(维也纳)．Hewas also a man full of humour(幽默)． Once, at his 70th birthday party, a friend asked Freud if he could put his work into several words．"Well,"saidFreud, "we take the sick out of their trouble and return them to the common suffering．" As a devoted ( 忠实的) son, Freud often visited his old mother．Hismother usually spent her summers in asmall mountain town in Austria(奥地利)．TheKing Josef usually spent his summers there, too．Oneday in thesummer, a band( 乐队)wasplaying a lively tune( 曲子)whenFreud’s mother was sitting at the window and watc-hing the people singing and dancing on Main Street．Theold woman had a poor memory．Sheheard the band playing, but forgot it was the King’ s birthday．Freudwas visiting his mother on her 95th birthday．Hetold his mother,"Mama, the band is playing for your birthday．"She believed him and had a wonderful day． From what Freud said at his 70th birthday party, we can see that he was ______．