熱血背包客莊ㄟ

Fossils of the coral Acrocora palmata that date from the last period when glaciers grew and consequently spread from the polar regions are found at ocean depths far greater than those at which A. palmata can now survive. Therefore, although the fossilized A. palmata appears indistinguishable from A. palmata now living, it must have differed in important respects to have been able to live in deep water.

The argument depends on the assumption that

　　(A) no fossils of the coral A. palmata have been found that date from periods when glaciers were not spreading from the polar regions

　　(B) geological disturbances since the last period during which glaciers spread have caused no major downward shift in the location of A. palmata fossils

　　(C) A. palmata now live in shallow waters in most of the same geographical regions as those in which deep-lying A. palmata fossils have been found

　　(D) A. palmata fossils have been found that date from each of the periods during which glaciers are known to have spread from the polar region

　　(E) A. palmata can live at greater depths where the ocean temperature is colder than they can where the ocean temperature is warmer

要來解這種披著英文皮卻在考邏輯的考試，還是要針對文章的每個句子做分析，每個字都是重要的資訊，這裡有一小段話，這個小的argument一定會遵循所謂的argument寫作規則，所以第一：argument=premises+conclusion，就是一個辯論一定是由數個前提加上一個結論組成，而這數個前提可能是對的可能是錯的，要自行判斷出前提跟結論有關聯支持性，假設驗證後每個前提都是真的（truth），再加上整個argument是有效的斬釘截鐵的（valid），這樣如此一來整個argument才是個健康（sound）的argument，因為前提的定義就是要支持或提供立足點給結論的，而結論定義就是在這段辯論當中你相信的這件事情是真的的這個句子。第二：這也帶出了一個現象，往往前提會有所謂的不可爭論性，雖然不一定，但是很多的前提都會用證據來表示呈現，然後用這些證據來支持你認為是對的事情（又稱個人觀點），所以這也是另一種形式：一個論辯＝觀點＋證據（論點＋論據）。好的，大概知道規則之後就開始解這題吧

本題要問的是assumption，他的意思就是這辯論當中，存在著一個邏輯缺陷，但是只要加上一個『前提』，就可以使得這個conclusion很完美，並讓整個argument是valid的，注意：argument沒有對跟錯，只有好跟壞，在批判性思維當中的規則就是請找出一個『隱藏性前提』就是了，文章作者不知不覺了加上一個預設立場。

分析：

premise : Fossils of the coral Acrocora palmata that date from the last period when glaciers grew and consequently spread from the polar regions are found at ocean depths far greater than those at which A. palmata can now survive.

這段話當中一些文法上的作用使得其實可以再細分的前提把它搞再一起，所以我就不分開了，因為考試不允許化簡為繁，不然時間不夠用，原本呈現應該是

Ｐ1: Fossils of the coral Acrocora palmata that date from the last period when glaciers grew and consequently spread from the polar regions are found

P2: Fossils of the coral Acrocora palmata (...中間的關代我就省略了...) are at ocean depths

P3: Fossils of the coral Acrocora palmata are far greater than Fossils of the coral Acrocora palmata at which A. palmata can now survive.

這個前提講的主幹就是有一些冰河時期的化石被發現在深海的大鳳梨裡，（喔是誰住在深海的大鳳梨裡，鬆鬆黃黃伸縮自如）阿不是是比起現在這些還沒變成化石的ＡＰ棲息地還要遠的深海裡，這是全部前提內容，然後看到Therefore，就要立刻判斷他是結論，不然考試報名就別了，已經報名就申請退費吧。

conclusion: Therefore, although the fossilized A. palmata appears indistinguishable from A. palmata now living, it must have differed in important respects to have been able to live in deep water.

結論是一整句話，不能把他跟讓步句給分開，所以簡單抓主幹就是，結論就是，必定有不同之處，看你就是跟別人不一樣，是個百年難得一見的練武奇才。

分析完之後就是找到裡面的隱性前提，也就是預設立場了，這是題目要找的，所以回想一下argument的定義，前提不管好壞，一定支持結論，結碖一定是你覺得是真的的事情，最後前提和結論兩者有關連，而我們前提（premises）中強調的事情是at ocean depths，還有 far greater than, now，作者認為發現地和現在居住地有一段距離，就是地點才使他認為一定有不同之處，這時對前提打上問號之後，你會發現，ＡＰ一定永遠都在這個地方嗎？所以選項中跟地點變化有關的只有（Ｂ）了，要確定ＡＰ永遠在那個地方，才能做出結論啊，就是所謂的當前提是確定無誤的時候，結論的描述有會有正確的可能性，正所謂結論具有所謂的truth preserving (B) geological disturbances since the last period during which glaciers spread have caused no major downward shift in the location of A. palmata fossils，選（Ｂ）

補充：

(A) no fossils of the coral A. palmata have been found that date from periods when glaciers were not spreading from the polar regions

這個選項是針對時間限定，所以抓錯重點了

(C) A. palmata now live in shallow waters in most of the same geographical regions as those in which deep-lying A. palmata fossils have been found

看到the same就別選了，這在跟『前提』唱反調，強詞奪理，已存在的事實不能去改變，這樣不會扭曲論辯（distortion）

(D) A. palmata fossils have been found that date from each of the periods during which glaciers are known to have spread from the polar region

也是針對時間限定，抓錯重點了

(E) A. palmata can live at greater depths where the ocean temperature is colder than they can where the ocean temperature is warmer

這雖然有對地點做說明，但是這是用達爾文適者身存的角度去探討，假設都適應了，那怎麼可能會有結論的『不同』出現，所以也是一個扭曲。

我認為GRE的錯誤選項是定義上的問題，角色扮演上的錯誤，而不是翻譯內容上的瑕疵讓他產生錯誤，所以要從定義著手才是王道，以上個人筆記希望有幫助到大家，文章內容中英夾雜請見諒，有誤再請指教!!