who is nuts?

In a hospital for mentally disturbed people, when
the doctor walked into the room of a patient, he
saw him dangling from the ceiling. Being frightened,
he called the nurse to come and pull him down for
fear that the man might fall to his death. The nurse
said: "Doctor, every day this patient thinks that he
is a lamp, therefore, he often hangs from the ceiling!"
The doctor said: "No, you have to pull him
down at once; otherwise, he'll die if he falls down."
After a pause, the nurse answered:
"But the light will go out after I pull him down!

一家智障的病院里，醫師走進一個病人的房間，
發現病人正吊在天花板上晃來晃去，醫師怕病人
會摔死，叫護士趕緊把病人拉下來。護士說：
「醫生，這個病人每天都認為自己是一盞燈，
所以常常把自己吊在天花板上。」
醫師說：「不行，你還是得馬上把他拉下來，
免得他摔死。」護士停頓了一下，
說：「可是，如果我把他拉下來，燈不就熄了嗎？