這是我在Wikipedia看到的，應該是解釋的比較清楚，客觀的

實在比較笨，看完電影后一頭霧水，+上豆瓣影評又有那麼多觀點，我就上網搜了下關於S.Island的評論
片中多次提到：Lobotomy 前腦葉白質切除術，這個手術就是把人的大腦用於性格的部份廢除（前腦管的是性格），我覺得就是做了手術之後和植物人沒什麼區別，不過這手術我看Wiki上說此手術已經廢除了，似乎藥物就可以做到手術的療效了。
我嘗試著解釋下Lobotomy和本片的關係
在1950年的時候，前腦葉白質切除術還是被廣泛的應用者，不過不同的意見已經被提出了有些醫生認為精神病不是不可治療的，而是可以用藥物或者教育就能達到。從很早以前精神病就是被認為像腫瘤一樣要被切除，所以這個理論根深蒂固的在人們心裡，而本片就是當兩個不同的意見交匯的時候，一場辯論開始了
很關鍵的2句： "die as a good man"：被lobotomize，而活著像植物人一樣，亦或者是"live as a monster"：未被lobotomize，而活著像個精神病人，本片並未點名Teddy的結局是如何(小說中Teddy被lobotomize了），還有個事實就是Teddy殺了他老婆，而他所面對的是接受還是不接受，接受就是"live as a monster"，反之則是"die as a good man"，希望能用我淺薄的文字來表達出原文的意圖

In the 2010 馬丁 Scorsese psychological mystery-thriller film Shutter Island based on the novel of the same name set in the 1950s when lobotomy was considered an appropriate procedure by many in the psychiatric community, the main character, found to be criminally insane, is given the choice of facing up to the reality that he murdered his wife or be lobotomized. In the novel, it is clear he receives a lobotomy involuntarily after relapsing into insanity whereas the movie is ambiguous as to whether he faked his relapse in order to "die as a good man" by being lobotomized rather than "live as a monster" without the treatment. Dr. 詹姆士 Gilligan, a past director of Massachusetts' prison mental hospital and serving as a technical advisor stated:
「 We worked together to make sure the story reflected a true war that was going on in the mid-20th century within the psychiatric community: a war between those clinicians who wanted to treat these patients with new forms of psychotherapy, education and medicine, and those who regarded the violent mentally ill as incurable and advocated controlling their behavior by inflicting irreversible brain damage, including indiscriminate use of shock treatment and crude forms of brain surgery, such as lobotomies.

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