The report stated "Then all of a suddin I remembered the operashun and me getting smart and I said holy smoke I reely pulled a Charlie Gordon that time. I went away beforeshe come back to the room. Thats why im going away from New York for good." Implying that he was leaving so he wasn't sad.

Charlie was not happy at the end like he was at the begining. At the end, he had to leave just so he wouldn't remember his operation. He was sad about it and left as soon as he remembered it.

Charlie was happier at the begining of the story because he didn't have to live with once being smart, and he didn't have to leave just so his friends wouldn't be sorry for him and so he wouldn't be sorry for himself. As soon as he remembered the operation, he decided he should leave and not come back so he could forget about the things that recently happened so he wouldn't be sad. He said that him remembering the operation and him getting smart is why he left for New York.