| 帕拉圖 | |||
| 阿裏斯托勒斯 | |||
閱讀柏拉圖 Plato在诗海的作品!!! | |||
也譯為帕拉圖
拼音：Bó lā tú
英譯：Plato
希臘語：Πλάτων
(約公元前427年－前347年）
古希臘哲學家，也是全部西方哲學乃至整個西方文化最偉大的哲學家和思想傢之一，他和老師蘇格拉底，學生亞裏士多德並稱為古希臘三大哲學家。
【簡介】
名字的由來：柏拉圖原名阿裏斯托勒斯，卻又何以改稱“柏拉圖”？溯其源，阿裏斯托勒斯自幼身體強壯，胸寬肩闊。因此體育老師就替他取了“柏拉圖”一名，“柏拉圖”希臘語意為“寬闊”。後來，柏拉圖的名字被延用下來，流行至今。
柏拉圖出身於雅典貴族，青年時從師蘇格拉底。蘇氏死後，他遊歷四方，曾到埃及、小亞細亞和意大利南部從事政治活動，企圖實現他的貴族政治理想。公元前387年活動失敗後逃回雅典，在一所稱為阿加德米（Academy）的體育館附近設立了一所學園，此後執教40年，直至逝世。他一生著述頗豐，其教學思想主要集中在《理想國》（The Republic）和《法律篇》中。
柏拉圖是西方客觀唯心主義的創始人，其哲學體係博大精深，對其教學思想影響尤甚。柏拉圖認為世界由“理念世界”和“現象世界”所組成。理念的世界是真實的存在，永恆不變，而人類感官所接觸到的這個現實的世界，衹不過是理念世界的微弱的影子，它由現象所組成，而每種現象是因時空等因素而表現出暫時變動等特徵。由此出發，柏拉圖提出了一種理念論和回憶說的認識論，並將它作為其教學理論的哲學基礎。
柏拉圖認為人的一切知識都是由天賦而來，它以潛在的方式存在於人的靈魂之中。因此認識不是對世界物質的感受，而是對理念世界的回憶。教學目的是為了恢復人的固有知識。教學過程即是"回憶"理念的過程。在教學中，柏拉圖重視對普遍、一般的認識，特別重視學生思維能力的培養，認為概念、真理是純思維的産物。同時他又認為學生是通過理念世界在現象世界的影子中纔得以回憶起理念世界的，承認感覺在認識中的刺激作用。他特別強調早期教育和環境對兒童的作用。認為在幼年時期兒童所接觸到的事物對他有着永久的影響，教學過程要通過具體事物的感性啓發，引起學生的回憶，經過反省和思維，再現出靈魂中固有的理念知識。就此而言，柏拉圖的教學認識是一種先驗論。
柏拉圖的教學體係是金字塔形。為了發展理性，他設立了全面而豐富的課程體係，他以學生的心理特點為依據，劃分了幾個年齡階段，並分別授以不同的教學科目。0一3歲的幼兒在育兒所裏受到照顧。3一6歲的兒童在遊樂場內進行故事、遊戲、唱歌等活動。6歲以後，兒童進入初等學校接受初級課程。在教學內容上，柏拉圖接受了雅典以體操鍛煉身體，以音樂陶冶心靈的和諧發展的教育思想，為兒童安排了簡單的讀、寫、算、唱歌，同時還十分重視體操等體育訓練項目。17一20歲的青年升入國立的“埃弗比” 接受軍事教育，並結合軍事需要學習文化科目，主要有算術、幾何、天文、音樂。20一30歲，經過嚴格挑選，進行10年科學教育，着重發展青年的思維能力，繼續學習"四科"，懂得自然科學間的聯繫。30歲以後，經過進一步挑選，學習5年，主要研究哲學等。至此，形成了柏拉圖相對完整的金字塔形的教學體係。
根據其教學目的，柏氏吸收和發展了智者的‘三藝’及斯巴達的軍事體育課程，也總結了雅典的教學實踐經驗，在教育史上第一次提出了“四科”（算術、幾何、天文、音樂），其後便成了古希臘課程體係的主幹和導源，支配了歐洲的中等與高等教育達1500年之久。
柏拉圖認為，每門學科均有其獨特的功能，凡有所學，皆會促成性格的發展。在17歲之前，廣泛而全面的學科內容是為了培養公民的一般素養，而對於未來的哲學家來講，前面所述的各門學科都是學習辯證法必不可少的知識準備。文法和修辭是研究哲學的基礎；算術是為了鍛煉人的分析與思考能力：學習幾何、天文，對於航海、行軍作戰、觀測氣候、探索宇宙十分重要；學習音樂則是為了培養軍人的勇敢和高尚的道德情操。同時，他還很重視選擇和淨化各種教材，如語言、故事、神話、史詩等，使其符合道德要求，以促進兒童心智之發展。
就教學方法而言，柏拉圖師承蘇格拉底的問答法，把回憶已有知識的過程視為一種教學和啓發的過程。他反對用強製性手段灌輸知識，提倡通過問答形式，提出問題，揭露矛盾，然後進行分析、歸納、綜合、判斷，最後得出結論。
理性的訓練是柏拉圖教學思想的主要特色。在教學過程中，柏拉圖始終是以發展學生的思維能力為最終目標的。在《理想國》中，他多次使用了“反思”（reflection）和“沉思”（contemplation）兩詞，認為關於理性的知識唯有憑藉反思、沉思才能真正融會貫通，達到舉一反三。感覺的作用衹限於現象的理解，並不能成為獲得理念的工具。因此，教師必須引導學生心思凝聚，學思結合，從一個理念到達另一個理念，並最終歸給為理念。教師要善於點悟、啓發、誘導學生進入這種境界，使他們在“苦思冥想”後“頓開茅塞”，喜獲“理性之樂”。這與蘇格拉底的助産術有異麯同工之妙。
柏拉圖的教學思想幾乎涉及到教學領域中的所有重要方法。他第一個確定了心理學的基本劃分，並使之與教學密切聯繫起來。他繼承並發展了斯巴達的依據年齡特徵劃分教學階段的教學理論，在教學的具體內容、形式、方法和手段上則更多地總結與采用了雅典的經驗，提出了全面、和諧發展的課程體係。他十分註重在教學中發展學生的思維能力，強調探討事物的本質，這些都給了後世教育傢們以巨大的影響和啓迪。
但是，柏拉圖誇大了理性發展在教學中的意義。他主張的通過回憶和沉思冥想以致知的教學過程，反映了其對掌握知識理解中的唯心主義傾嚮。特別是他把理性絶對化、孤立化，使感覺和理性之間對立起來的思想，以致成了中世紀經院派教條主義教學方法的理論基礎。他有一句名言：不知道自己的無知，乃是雙倍的無知。
【生平】
一般推測柏拉圖出生的年份應該是在公元前427年或前428年的5月或12月（如同其他早期的西方哲學家，他的出生日期也依然未知）。柏拉圖生於一個較為富裕的貴族家庭，他的父親是阿裏斯通（Ariston）、母親是剋裏提俄涅（Perictione），他在傢中排行老四。他的家庭宣稱是古雅典國王的後代，他也是當時雅典知名的政治傢柯裏西亞斯（Critias）的侄子，不過兩人之間的關係也仍有爭議。依據後來第歐根尼·拉爾修的說法，柏拉圖的原名為亞裏斯多剋勒斯（Aristokles），後來因為他強壯的身軀而被稱為柏拉圖（在希臘語中，Platus一詞是“平坦、寬闊”等意思）。但第歐根尼也提起了其他的說法，柏拉圖這個名字也可能是來自他流暢寬廣（platutês）的口才、或因為他擁有寬廣的前額。由於柏拉圖出色的學習能力和其他才華，古希臘人還稱贊他為阿波羅之子，並稱在柏拉圖還是嬰兒的時候曾有蜜蜂停留在他的嘴唇上，纔會使他口才如此甜蜜流暢。
公元前399年，蘇格拉底受審並被判死刑，柏拉圖對現存的政體完全失望，於是開始遊遍意大利、西西裏島、埃及、昔蘭尼等地以尋求知識。在四十歲時（約公元前387年）他結束旅行返回雅典，並在雅典城外西北郊的聖城阿卡德米創立了自己的學校——阿卡德米學園（Academy），學院成為西方文明最早的有完整組織的高等學府之一，後世的高等學術機構也因此而得名，也是中世紀時在西方發展起來的大學的前身。 阿卡德米坐落於一處曾為希臘傳奇英雄阿卡得摩斯（Academus）住所的土地上，因而以此命名。學院存在了900多年，直到公元529年被查士丁尼大帝關閉為止。學院受到畢達哥拉斯的影響很大，課程設置類似於畢達哥拉斯學派的傳統課題，包括了算術、幾何學、天文學以及聲學。據說，柏拉圖在學園門口立了塊碑：“不懂幾何者不準入內”。學院培養出了許多知識分子，其中最傑出的是亞裏士多德。
除了荷馬之外，柏拉圖也受到許多那之前的作傢和思想傢的影響，包括了畢達哥拉斯所提出的“和諧”概念，以及阿那剋薩哥拉教導蘇格拉底應該將心靈或理性作為判斷任何事情的根據；巴門尼德提出的連結所有事物的理論也可能影響了柏拉圖對於靈魂的概念。
【年表】
一、 成長時期28年：
公元前427年 柏拉圖出生（奧林匹剋88屆第一年），傢世顯赫，此年即伯羅奔尼撒戰爭爆發後4年，伯裏剋利死後第二年，蘇格拉底42歲（是年西西裏萊翁蒂尼（Leontini）邦人高爾吉亞來雅典求援，告敘拉古入侵其邦）。
公元前423年 4歲，阿裏斯托芬《雲》上演，蘇格拉底在場觀賞，當場現身示衆，態度自若。
公元前421年 6歲，據說是《理想國》發生時間（或所托時間）。
公元前420年 7歲，進狄奧尼索斯學校，識字，聽荷馬等詩作。
公元前411年 16歲，普羅塔哥拉被400人大會中人指控使人不信神，逃出雅典，在往西西裏途中遇難（前此哲學家受迫害或驅逐、處死、或自願放逐的還有阿那剋薩哥拉，畢達哥拉斯、赫拉剋利特）。
公元前409-404年 估計到過騎兵執勤，據說參加過3次戰役。
公元前408年 高爾吉亞在第93屆奧林匹亞運動會上發表演說，呼籲雅典和斯巴達團结起來對付波斯。
公元前407年 20歲跟隨蘇格拉底學習，此前曾嚮剋拉底魯學習赫拉剋利特哲學；嚮赫莫根尼學習巴門尼德哲學。據說曾想寫戲劇，給蘇格拉底看，被否定。
公元前405年 敘拉古狄奧尼索斯推翻民主，建立僭主政權。
公元前404年 23歲，伯羅奔尼撒戰爭結束，雅典30僭主，柏拉圖一度想從政，後失望。
公元前399年 28歲，蘇格拉底受審（柏拉圖在場）並被處死，就死時因病不在（太傷心？）。
二、遊學12年
公元前398年 柏拉圖與其他蘇格拉底的弟子紛紛離開雅典到外地避風，到過西西裏、意大利、埃及。
公元前392年 35歲，在這前後，撰寫早期對話：《申辯》、《剋力同》、《遊敘弗倫》、《拉齊斯》、《呂西斯》、《查米迪斯篇》。
伊索剋拉底在雅典辦學園，教演講術。
公元前390年 出訪：畢達哥拉斯學派掌握的政權等。
公元前388年 訪敘拉古狄奧尼索斯一世，結識其小舅子（女婿）狄翁（時狄翁20歲），成為至交，（此其間據說曾得罪僭主被賣作奴隸，由安尼捨裏斯贖身）。
三、講學20年
公元前387年 40歲，回到雅典，開始個人講學，或說此年建立學園，此前後撰寫對話：《普羅塔哥拉》、《美諾》、《尤息德謨斯篇》。
又中期著作：《理想國》、《會飲》、《斐得若》、《費多》等最具戲劇性的對話。
公元前385年 （見陳表：蘇格拉底案的平反：控告人的死，立蘇格拉底雕像，但不一定真實。又陶行知1938到雅典參觀石牢，坐5分鐘以示敬仰，又寫詩“這位老人傢，為何也坐牢？歡喜說真話，假人都煩惱”，又杜汝輯、葉秀山文章談及此）。
公元前384年 43歲，亞裏士多德生，德謨斯提尼生。
公元前380年 大約在這些年，在雅典西北郊外的陶器區建立學園。“不懂幾何學者勿入此門。
公元前376年 高爾吉亞死。
公元前371年 底比斯軍在伊巴密濃達指揮下，大敗斯巴達。
公元前370年 德謨剋利特死，據說柏拉圖曾想購其書付之一炬。
四、晚年最後的政治嘗試及講學、著述：20年（或可再分兩段：政治、著述）
公元前367年 60歲，將學園交歐多剋索主持，自己帶弟子和友人第二次往敘拉古，當年老狄奧尼索斯死，狄翁攝政，此時柏拉圖已聲名遠播希臘及以外
亞裏士多德來雅典學習（據說講善，僅剩亞裏士多德一人聽）
公元前366年 狄奧尼索斯二世繼位，狄翁逃離，柏拉圖悵然離開敘拉古。
公元前363年 64歲，第三次往敘拉古，被扣留，被逐。
公元前357年 70歲，放棄政治活動，全力著述，晚期著作有：智者、政治傢、斐裏布、蒂邁歐篇。
公元前356年 亞歷山大大帝出生。
公元前348年 晚年最後的著作是：法律篇，伊璧諾米篇續篇，剛開篇即去世。
公元前347年 春季（三月？）去世，遺囑對用於校捨的房産，不許出售、轉讓。留下四傢奴，釋放一奴隸，財産很少。
公元前344-343年 狄奧尼索斯二世最後被推翻，亞裏士多德任亞歷山大教師。
比較孔子（前551-479）：
15-30歲，初仕魯，做小官，“工讀”時期：15年
30-50歲，專一講學期，34歲授徒講學： 20年
51-54歲，再仕魯，任司寇，從政期： 4年
55-68歲，周遊列國時期： 14年
69-73歲，晚年整理古籍： 5年
【地位】
柏拉圖與他的學生亞裏士多德比起來，在西方得到更多的尊重和註意。因為他的作品是西方文化的奠基文獻。在西方哲學的各個學派中，很難找到沒有吸收過他的著作的學派。在後世哲學家和基督教神學中，柏拉圖的思想保持着巨大的輻射力。有的哲學史傢認為，直到近代，西方哲學纔逐漸擺脫了柏拉圖思想的控製。
公元12世紀以前，亞裏士多德的學說一直被教廷排斥，甚至歐洲已經不再流傳亞裏士多德的著作。當時，柏拉圖的學說占統治地位，因為聖奧古斯丁藉用和改造了柏拉圖的思想，以服務神學教義。直到13世紀，托馬斯·阿奎那利用亞裏士多德的學說解釋宗教教義，建立了煩瑣和龐大的經院哲學。亞裏士多德纔重新被重視。
柏拉圖的理論，被1949年後的中華人民共和國官方認為是唯心主義的。但他對西方哲學的啓蒙作用被普遍認可，也因為他卓越的人格而備受尊重。
【主要著作】
柏拉圖才思敏捷，研究廣泛，著述頗豐。以他的名義流傳下來的著作有40多篇，另有13封書信。柏拉圖的主要哲學思想都是通過對話的形式記載下來的。在柏拉圖的對話中，有很多是以蘇格拉底之名進行的談話，因此人們很難區分哪些是蘇格拉底的思想，哪些是柏拉圖的思想。經過後世一代代學者艱苦細緻的考證，其中有24篇和4封書信被確定為真品，主要有：
I《伊壁鳩魯篇》《蘇格拉底的申辯》 《剋力同篇》 《斐多篇》
II《剋堤拉斯篇》《泰阿泰德篇》《智士篇》 《政治傢篇》
III《巴曼尼得斯篇》《菲力帕斯篇》 《饗宴篇》《斐德羅篇篇》
IV《阿奇拜得篇之一》《阿奇拜得篇之二》 《高爾吉亞篇》
《智者篇》《政治傢篇》《斐利布斯篇》《法律篇》《理想國》
《蘇格拉底的申辯》 《理想國》 《巴曼尼得斯篇》《蘇格拉底之死》
柏拉圖偽作也有重要的學術意義，以下著作被認為是後世偽托的作品：
《米諾斯》（Minos）《歐律剋西亞斯》（Eryxias）《泰戈斯》（Theages）《剋裏托芬》（Cleitophon）《愛人》（Lovers）
柏拉圖的著作大多是用對話體裁寫成的，人物性格鮮明，場景生動有趣，語言優美華麗，論證嚴密細緻，內容豐富深刻，達到了哲學與文學、邏輯與修辭的高度統一，不僅在哲學上而且在文學上亦具有極其重要的意義和價值。
目前使用廣泛的是《柏拉圖全集》（四捲本），人民出版社出版，王曉朝譯。
【思想概述】
柏拉圖認為任何一種哲學要能具有普遍性，必須包括一個關於自然和宇宙的學說在內。柏拉圖試圖掌握有關個人和大自然永恆不變的真理，因此發展一種適合併從屬於他的政治見解和神學見解的自然哲學。
柏拉圖認為，自然界中有形的東西是流動的，但是構成這些有形物質的“形式”或“理念”卻是永恆不變的。柏拉圖指出，當我們說到“馬”時，我們沒有指任何一匹馬，而是稱任何一種馬。而“馬”的含義本身獨立於各種馬（“有形的”），它不存在於空間和時間中，因此是永恆的。但是某一匹特定的、有形的、存在於感官世界的馬，卻是“流動”的，會死亡，會腐爛。這可以作為柏拉圖的“理念論”的一個初步的解說。
柏拉圖認為，我們對那些變換的、流動的事物不可能有真正的認識，我們對它們衹有意見或看法，我們唯一能夠真正瞭解的，衹有那些我們能夠運用我們的理智來瞭解的“形式”或者“理念”。因此柏拉圖認為，知識是固定的和肯定的，不可能有錯誤的知識。但是意見是有可能錯誤的。
在柏拉圖的《理想國》中，有一個著名的洞穴比喻來解釋理念論：有一群囚犯在一個洞穴中，他們手腳都被捆綁，身體也無法轉身，衹能背對着洞口。他們面前有一堵白墻，他們身後燃燒着一堆火。在那面白墻上他們看到了自己以及身後到火堆之間事物的影子，由於他們看不到任何其他東西，這群囚犯會以為影子就是真實的東西。最後，一個人掙脫了枷鎖，並且摸索出了洞口。他第一次看到了真實的事物。他返回洞穴並試圖嚮其他人解釋，那些影子其實衹是虛幻的事物，並嚮他們指明光明的道路。但是對於那些囚犯來說，那個人似乎比他逃出去之前更加愚蠢，並嚮他宣稱，除了墻上的影子之外，世界上沒有其他東西了。
柏拉圖利用這個故事來告訴我們，“形式”其實就是那陽光照耀下的實物，而我們的感官世界所能感受到的不過是那白墻上的影子而已。我們的大自然比起鮮明的理型世界來說，是黑暗而單調的。不懂哲學的人能看到的衹是那些影子，而哲學家則在真理的陽光下看到外部事物。
柏拉圖的《理想國》還嚮我們描繪出了一幅理想的烏托邦的畫面，柏拉圖認為，國傢應當由哲學家來統治。柏拉圖的理想國中的公民劃分為衛國者、士兵和普通人民三個階級。衛國者是少部分管理國傢的精英。他們可以被繼承，但是其他階級的優秀兒童也可以被培養成衛國者，而衛國者中的後代也有可能被降到普通人民的階級。衛國者的任務是監督法典的製定和執行情況。為達到該目的柏拉圖有一整套完整的理論。他的理想國要求每一個人在社會上都有其特殊功能，以滿足社會的整體需要。但是在這個國傢中，女人和男人有着同樣的權利，存在着完全的性平等。政府可以在為了公衆利益時撒謊。每一個人應該去做自己份內的事而不應該打擾到別人。在今天看來，柏拉圖描繪的理想國是一個可怕的極權主義國傢。但是“理想國其實是用正確的方式管理國傢的科學家的觀點”，柏拉圖本人並沒有試圖實現理想國中的國傢機器。
柏拉圖在《律法》(The Laws)則指出，“憲法國傢”是僅次於理想國的最好的國傢。他在該書中同樣指出，婦女和男人應該得到同樣的尊重和訓練。
柏拉圖企圖使天文學成為數學的一個部門。他認為：“天文學和幾何學一樣，可以靠提出問題和解决問題來研究，而不去管天上的星界。”柏拉圖認為宇宙開頭是沒有區別的一片混沌。這片混沌的開闢是一個超自然的神的活動的結果。依照柏拉圖的說法，宇宙由混沌變得秩序井然，其最重要的特徵就是造物主為世界製定了一個理性方案；關於這個方案付諸實施的機械過程，則是一種想當然的自然事件。
柏拉圖的宇宙觀基本上是一種數學的宇宙觀。他設想宇宙開頭有兩種直角三角形，一種是正方形的一半，另一種是等邊三角形的一半。從這些三角形就合理地産生出四種正多面體，這就組成四種元素的微粒。火微粒是正四面體，氣微粒是正八面體，水微粒是正二十面體，土微粒是立方體。第五種正多面體是由正五邊形形成的十二面體，這是組成天上物質的第五種元素，叫做以太。整個宇宙是一個圓球，因為圓球是對稱和完善的，球面上的任何一點都是一樣。宇宙也是活的，運動的，有一個靈魂充溢全部空間。宇宙的運動是一種環行運動，因為圓周運動是最完善的，不需要手或腳來推動。四大元素中每一種元素在宇宙內的數量是這樣的：火對氣的比例等於氣對水的比例和水對土的比例。萬物都可以用一個數目來定名，這個數目就是表現它們所含元素的比例。
【政治思想】
在《理想國》中，柏拉圖設計了一幅正義之邦的圖景：國傢規模適中，以站在城中高處能將全國盡收眼底，國人彼此面識為度。柏拉圖認為國傢起源於勞動分工，因而他將理想國中的公民分為治國者、武士、勞動者3個等級，分別代表智慧、勇敢和欲望3種品性。治國者依靠自己的哲學智慧和道德力量統治國傢;武士們輔助治國，用忠誠和勇敢保衛國傢的安全；勞動者則為全國提供物質生活資料。3個等級各司其職，各安其位。在這樣的國傢中，治國者均是德高望重的哲學家，衹有哲學家才能認識理念，具有完美的德行和高超的智慧，明了正義之所在，按理性的指引去公正地治理國傢。治國者和武士沒有私産和家庭，因為私産和家庭是一切私心邪念的根源。勞動者也絶不允許擁有奢華的物品。理想國還很重視教育，因為國民素質與品德的優劣决定國傢的好壞。柏拉圖甚至設想在建國之初就把所有10歲以上的人遣送出國，因為他們已受到舊文化的熏染，難以改變。全體公民從兒童時代開始就要接受音樂、體育、數學到哲學的終身教育。教育內容要經嚴格選擇，荷馬、赫西俄德的史詩以及悲劇詩人們的作品，一律不準傳入國境，因為它們會毒害青年的心靈。柏拉圖自稱這是“第一等好”的理想國，其他的政體都是這一理想政體的蛻變。理想政體由於婚配的不善引起3個等級的混雜，導致爭鬥，軍人政體（Timocracy）隨之興起。軍人政體中， 少數握有權勢者聚斂財富，形成寡頭政體（Oligarchy）。貧富矛盾的尖銳化導致民衆的革命，産生民主政體（Democracy）。民主政體發展到極端時又會被僭主政體（Tyranny）所取代。
《政治傢篇》約作於柏拉圖後兩次去敘拉古之間（公元前367～前361），這是他在敘拉古的政治實踐受到挫折，思想發生變化的時期。《政治傢篇》主旨是討論真政治傢及政治的定義。柏拉圖在這篇對話中提出了政治中道、混合的概念；首次明確論述了法律的作用並以法律作為劃分政體的標準。他認為，真政治傢（哲學王）無需用法律統治，但現實中真政治傢極為罕見，即使有真政治傢，法律也還有一定的作用。因為政治不僅是一種藝術，亦是一門科學。法律對於政治傢，猶如教練和醫生的訓練方案和處方一樣，法律雖然在理論上是荒謬的，在實踐中卻是必要的。
柏拉圖在其最後的作品《法律篇》中進一步發揮了關於法律的作用的思想。從理想出發，他推崇哲學王的統治，“沒有任何法律或條例比知識更有威力”；從現實出發，他強調人類必須有法律並且遵守法律，否則他們的生活將如同最野蠻的獸類。在這一思想指導下，他在12捲的《法律篇》中，設計了他的“第二等好”的城邦，包括地理環境、疆域大小、人口規模與來源、國傢經濟生活、階級結構、政治制度、法律等細則。由於指導思想的變化，第二等好的城邦與《理想國》中的正義之邦相比，在具體措施上有很大區別。主要有：政治制度由哲學王執政的賢人政體轉為混合政體，以防止個人專權。《理想國》主張統治者實行公産、公妻、公餐、公育製，《法律篇》則恢復了私有財産和家庭。《理想國》中劃分公民等級是依照其先天稟賦的優劣，而《法律篇》則是按照後天財産的多寡。
【教育觀】
柏拉圖還是西方教育史上第一個提出完整的學前教育思想並建立了完整的教育體係的人。柏拉圖中年開始從事教育研究活動。他從理念先於物質而存在的哲學思想出發，在其教育體係中強調理性的鍛煉。他要求3～6歲的兒童都要受到保姆的監護，會集在村莊的神廟裏，進行遊戲、聽故事和童話。柏拉圖認為這些都具有很大的教育意義。7歲以後，兒童就要開始學習軍人所需的各種知識和技能，包括讀、寫、算、騎馬、投槍、射箭等等。從20～30歲，那些對抽象思維表現特殊興趣的學生就要繼續深造，學習算術、幾何、天文學與和聲學等學科，以鍛煉他的思考能力，使他開始探索宇宙的奧妙。柏拉圖指出了每門學科對於發展抽象思維的意義。他主張未來的統治者在30歲以後，要進一步學習辯證法，以洞察理念世界。經過5年後，他就可以成為統治國傢的哲學王了。
在他的奴隸主教育學體係中，體育占有重要的地位。柏拉圖對婦女體育也很重視。他認為：“做女孩的應該練習各種跳舞和角力；結婚以後，便要參加戰鬥演習、行營布陣和使用武器……因為一旦當所有的軍隊出動去打敵人的時候，她們就能保衛兒童和城市” （《柏拉圖論教育》）。在柏拉圖的論述中，幾乎涉及到當時體育的各個方面。他認為，體育應包括教育手段和健康術。他對當時雅典出現的競技主義和競技職業化傾嚮曾給予猛烈的抨擊，同時也批評市民輕視體育的思想和態度。他主張心身和諧發展，強調“用體育鍛煉身體，用音樂陶冶心靈”。柏拉圖豐富的體育思想對後世體育的發展有深遠的影響。
【愛情觀】
柏拉圖和亞裏士多德是古希臘哲學家中最有影響的人，而在他們兩個人中間，柏拉圖對於後代所起的影響尤其來得大。柏拉圖著書以他的老師蘇格拉底之口表述說，當心靈摒絶肉體而嚮往着真理的時候，這時的思想纔是最好的。而當靈魂被肉體的罪惡所感染時，人們追求真理的願望就不會得到滿足。
在歐洲，很早就有被我們中國人稱之為“精神戀愛”的柏拉圖式的愛，這種愛認為肉體的結合是不純潔的是骯髒的，認為愛情和情欲是互相對立的兩種狀態，因此，當一個人確實在愛着的時候，他完全不可能想到要在肉體上同他所愛的對象結合。
在今天的人們看來，柏拉圖的愛情觀讓人不可思議。而有一位美國學者卻對今人所理解的這種柏拉圖的愛情觀，提出了新的見解。美國東西部社會學會主席、《美國家庭體製》一書的作者伊拉·瑞斯（Ira·reiss）經研究後認為，柏拉圖推崇的精神戀愛，實際上指的是同性之間的一種愛，也就是“同性戀”。古希臘人認為，同性戀的過程更多地是靈交、神交，而非形交。而在女性很少受教育的古希臘社會，男人很難從女人中找到精神對手。這就是柏拉圖偏重男性之間的愛情的原因。柏拉圖堅信"真正"的愛情是一種持之以恆的情感，而惟有時間纔是愛情的試金石，惟有超凡脫俗的愛，才能經得起時間的考驗。
而美國的社會學者對“柏拉圖式的愛情”是衹有神交的“純愛情”，還是雖有形交卻偏重神交的高雅愛情，也衆說紛紜。但有一點是可以肯定的，即柏拉圖認為愛情能夠讓人得到升華。他說，對活得高尚的男人來說，指導他行為的不是血緣，不是榮譽，不是財富，而是愛情。世上再也沒有一種情感像愛情那樣深植人心。一個處在熱戀中的人假如作出了不光彩的行為，被他的父親、朋友或別的什麽人看見，都不會像被自己的戀人看見那樣，使他頓時蒼白失色，失去一切的一切，無力面對自己愛的人和愛自己的人。
【柏拉圖名言】
·在短暫的生命裏尋找永恆
·愛是美好帶來的歡欣，智慧創造的奇觀，神仙賦予的驚奇。缺乏愛的人渴望得到它，擁有愛的人萬般珍惜它。
· 愛情，衹有情，可以使人敢於為所愛的人獻出生命；這一點，不但男人能做到，而且女人也能做到。
· 尊重人不應該勝過尊重真理。
· 時間帶走一切，長年纍月會把你的名字、外貌、性格、命運都改變。
· 拖延時間是壓製惱怒的最好方式。
· 初期教育應是一種娛樂，這樣纔更容易發現一個人天生的愛好。
· 人心可分為二，一部較善，一部較惡。善多而能製止惡，斯即足以雲自主，而為所譽美；設受不良之教育，或經惡人之熏染，緻惡這一部較大，而善這一部日益侵削，斯為己之奴隸，而衆皆唾棄其人矣。
· 良好的開端，等於成功的一半。
· 最有美德的人，是那些有美德而不從外表表現出來，仍然感到滿足的人。
· 好人之所以好是因為他是有智慧的，壞人之所以壞是因為人是愚蠢的。
· 一切背離了公正的知識都應叫做狡詐，而不應稱為智慧。
· 不知道自己的無知，乃是雙倍的無知。
· 沒有什麽比健康更快樂的了，雖然他們在生病之前並不曾覺得那是最大的快樂。
· 我們應該盡量使孩子們開始聽到的一些故事必定是有道德影響的最好的一課。
· 法律是一切人類智慧聰明的結晶，包括一切社會思想和道德。
· 衹有死者能看到戰爭的結束。
l 每天告訴自己一次：“我真的很不錯”。
l 生氣是拿別人做的錯事來懲罰自己。
l 每個在戀愛中的人都是詩人。
l 無論你從什麽時候開始，重要的是開始後就不要停止；無論你從什麽時候結束，重要的是結束後就不要悔恨。
l 衹要有信心，人永遠不會挫敗。
【柏拉圖主義】
柏拉圖主義（Platonism）是數學歷史上影響最大的數學哲學觀點，它起源於古希臘的柏拉圖，此後在西方數學界一直有着或明或暗的柏拉圖主義觀念，19世紀，它在數學界幾乎占了統治地。20世紀初，數學基礎三大學派的爭議剛趨平息，柏拉圖主義觀點又成為討論的熱點之一。
柏拉圖主義的基本觀點：數學的對象就是數、量、函數等數學概念，而數學概念作為抽象一般或“共相”是客觀存在着的。柏拉圖認為它們存在於一個特殊的理念世界裏，後世的柏拉圖主義者並不接受“理念論”，但也認為數學概念是一種特殊的獨立於現實世界之外的客觀存在，它們是不依賴於時間、空間和人的思維的永恆的存在。數學家得到新的概念不是創造，而是對這種客觀存在的描述；數學新成果不是發明，而是發現。與之相應的，柏拉圖主義認為數學理論的真理性就是客觀的由那種獨立於現實世界之外的存在决定的，而這種真理性是要靠“心智”經驗來理解，靠某種“數學直覺”來認識的，人們衹有通過直覺才能達到獨立於現實世界之外的“數學世界”。
由於認為數學概念是一種真實的存在，所以現代柏拉圖主義也被稱為“實在主義”。柏拉圖主義在西方近現代數學界有相當大的影響，一些數學巨匠如G．康托爾、羅素、哥德爾、布爾巴基學派基本上都持這種觀點。一般認為，所以如此不是偶然的，這是數學反映客觀世界，數學具有客觀真理性這一素樸信念在哲學上的反映。而正因為如此，柏拉圖主義對數學的歷史發展就具有一定的積極作用：它促使數學家們在自己的研究中采取客觀的科學的立場，而且，當某些高度抽象的數學理論因找不到現實原型而為人們所懷疑時，它也有可能給人們以一定的信念。儘管這種信念是盲目的，從而就有可能導致錯誤。
柏拉圖主義的錯誤是顯然的：把反映形式當作了認識對象；把抽象當作具體的客觀存在；認為一種思維形式本身是客觀的當然具有客觀的真理性。離開人的實踐來考察真理性必將導致謬誤。柏拉圖主義在哲學上是一種客觀唯心主義。”
宣稱信仰柏拉圖主義並非意味着接受柏拉圖的所有見解，而往往衹是對如下特定思想的認同，即理念形式是存在的、永恆的，並比世界中的現象更實在、更完美，甚至是唯一真正實在和完美的實體。這個體係還包括認為理念形式衹能由靈魂所認識等。
對柏拉圖主義的辯護有：語言對象的抽象描述的一般性和其所描述對象的特殊性的對比；數學對象的抽象和毫無疑問的精確性等。
柏拉圖主義中的理念形式在不同的情形下往往具有不同的意義。如：一類事物的名稱；數學對象；自然定律等。
它以理念論為中心，包括宇宙論方面的宇宙生成說，認識論方面的回憶說，倫理觀與社會政治觀方面的四主德與理想國的學說，美學方面的“摹本”說，探求理念體係的概念辯證法以及教育學說等。是歐洲哲學史上第一個龐大的客觀唯心主義體係，對後世西方哲學的影響極大。
【經濟學圖表：柏拉圖】
柏拉圖是為尋找影響産品質量的主要問題，用從高到低的順序排列成矩形，表示各原因出現頻率高低的一種圖表。
柏拉圖是美國品管大師朱蘭博士運用意大利經濟學家柏拉圖（Pareto）的統計圖加以延伸所創造出來的，柏拉圖又稱排列圖。
【柏拉圖式愛情】
柏拉圖式愛情，以西方哲學家柏拉圖命名的一種異性間的精神戀愛，追求心靈溝通，排斥肉欲。最早由Marsilio Ficino於15世紀提出，作為蘇格拉底式愛情的同義詞，用來指代蘇格拉底和他學生之間的愛慕關係。
柏拉圖認為：當心靈摒絶肉體而嚮往着真理的時候，這時的思想纔是最好的。而當靈魂被肉體的罪惡所感染時，人們追求真理的願望就不會得到滿足。當人類沒有對肉欲的強烈需求時，心境是平和的，肉欲是人性中獸性的表現，是每個生物體的本性，人之所以是所謂的高等動物，是因為人的本性中，人性強於獸性，精神交流是美好的、是道德的．
柏拉圖式的愛情有以下的意義:
1. 理想式的愛情觀 (比喻極為浪漫或根本無法實現的愛情觀)
2. 純精神的而非肉體的愛情
3. 男女平等的愛情觀
4. 在這世上有, 且僅有一個人, 對你而言, 她(他)是完美的, 而且僅對你而言是完美的。也就是說, 任何一個人, 都有其完美的對象, 而且衹有一個。
第一個意義最常被使用, 但其實是一個誤解。不過既然大傢都這樣用, 也就算是另一個意義了。這誤解來自於柏拉圖的一個有名的著作"理想國"。該書探討如何建構一個理想的國度, 因其或許過於理想化而難以實現, 故有人以此來詮釋何謂柏拉圖式的愛情。
第二個意義也經常被使用, 但基本上也是誤解。這誤解來自柏拉圖的形上學, 他認為思想的東西纔是真實的而我們看見的所謂的”真實世界”的東西反而不是真實的。
第三和第四個意義纔真的是柏拉圖的愛情觀或兩性觀
柏拉圖認為人們生前和死後都在最真實的觀念世界, 在那裏, 每個人都是男女合體的完整的人, 到了這世界我們都分裂為二。所以人們總覺得若有所失, 企圖找回自己的"另一半"(這個詞也來自柏拉圖的理論)。柏拉圖也用此解釋為什麽人們會有“戀情”。
在他的理論中, 沒有那一半是比較重要的, 所以, 男女是平等的。而且, 在觀念世界的你的原本的另一半就是你最完美的對象。他/她 就在世界的某個角落, 也正在尋找着你。
個人影響
柏拉圖在西方的地位.柏拉圖與他的學生亞裏士多德比起來，在西方得到更多的尊重和註意。因為他的作品是西方文化的奠基文獻。在西方哲學的各個學派中，很難找到沒有吸收過他的著作的學派。在後世哲學家和基督教神學中，柏拉圖的思想保持着巨大的輻射力。有的哲學史傢認為，直到近代，西方哲學纔逐漸擺脫了柏拉圖思想的控製。
公元12世紀以前，亞裏士多德的學說一直被教廷排斥，甚至歐洲已經不再流傳亞裏士多德的著作。當時，柏拉圖的學說占統治地位，因為聖奧古斯丁藉用和改造了柏拉圖的思想，以服務神學教義。直到13世紀，托馬斯・阿奎那利用亞裏士多德的學說解釋宗教教義，建立了煩瑣和龐大的經院哲學。亞裏士多德纔重新被重視。
他對西方哲學的啓蒙作用被普遍認可，也因為他卓越的人格而備受尊重。
因此，他被稱為是西方哲學的奠基人！
The safest general characterization of the European philosophical tradition is that it consists of a series of footnotes to Plato. I do not mean the systematic scheme of thought which scholars have doubtfully extracted from his writings. I allude to the wealth of general ideas scattered through them.
Plato's sophistication as a writer is evident in his Socratic dialogues; thirty-six dialogues and thirteen letters have been ascribed to him. Plato's writings have been published in several fashions; this has led to several conventions regarding the naming and referencing of Plato's texts. Plato's dialogues have been used to teach a range of subjects, including philosophy, logic, ethics, rhetoric, and mathematics.
Birth and family
The exact place and time of Plato's birth are not known, but it is certain that he belonged to an aristocratic and influential family. Based on ancient sources, most modern scholars believe that he was born in Athens or Aegina[b] between 429 and 423 BC.[a] His father was Ariston. According to a disputed tradition, reported by Diogenes Laertius, Ariston traced his descent from the king of Athens, Codrus, and the king of Messenia, Melanthus. Plato's mother was Perictione, whose family boasted of a relationship with the famous Athenian lawmaker and lyric poet Solon. Perictione was sister of Charmides and niece of Critias, both prominent figures of the Thirty Tyrants, the brief oligarchic regime, which followed on the collapse of Athens at the end of the Peloponnesian War (404–403 BC). Besides Plato himself, Ariston and Perictione had three other children; these were two sons, Adeimantus and Glaucon, and a daughter Potone, the mother of Speusippus (the nephew and successor of Plato as head of his philosophical Academy). According to the Republic, Adeimantus and Glaucon were older than Plato. Nevertheless, in his Memorabilia, Xenophon presents Glaucon as younger than Plato.
The traditional date of Plato's birth (428/427) is based on a dubious interpretation of Diogenes Laertius, who says, "When [Socrates] was gone, [Plato] joined Cratylus the Heracleitean and Hermogenes, who philosophized in the manner of Parmenides. Then, at twenty-eight, Hermodorus says, [Plato] went to Euclides in Megara." As Debra Nails argues, "The text itself gives no reason to infer that Plato left immediately for Megara and implies the very opposite." In his Seventh Letter Plato notes that his coming of age coincided with the taking of power by the Thirty, remarking, "But a youth under the age of twenty made himself a laughingstock if he attempted to enter the political arena." Thus Nails dates Plato's birth to 424/423.
According to some accounts, Ariston tried to force his attentions on Perictione, but failed in his purpose; then the god Apollo appeared to him in a vision, and as a result, Ariston left Perictione unmolested. Another legend related that, when Plato was an infant, bees settled on his lips while he was sleeping: an augury of the sweetness of style in which he would discourse philosophy.
Ariston appears to have died in Plato's childhood, although the precise dating of his death is difficult. Perictione then married Pyrilampes, her mother's brother, who had served many times as an ambassador to the Persian court and was a friend of Pericles, the leader of the democratic faction in Athens. Pyrilampes had a son from a previous marriage, Demus, who was famous for his beauty. Perictione gave birth to Pyrilampes' second son, Antiphon, the half-brother of Plato, who appears in Parmenides.
In contrast to his reticence about himself, Plato often introduced his distinguished relatives into his dialogues, or referred to them with some precision: Charmides has a dialogue named after him; Critias speaks in both Charmides and Protagoras; and Adeimantus and Glaucon take prominent parts in the Republic. These and other references suggest a considerable amount of family pride and enable us to reconstruct Plato's family tree. According to Burnet, "the opening scene of the Charmides is a glorification of the whole [family] connection... Plato's dialogues are not only a memorial to Socrates, but also the happier days of his own family."
Name
According to Diogenes Laërtius, the philosopher was named Aristocles after his grandfather, but his wrestling coach, Ariston of Argos, dubbed him "Platon", meaning "broad," on account of his robust figure. According to the sources mentioned by Diogenes (all dating from the Alexandrian period), Plato derived his name from the breadth (platytês) of his eloquence, or else because he was very wide (platýs) across the forehead. In the 21st century some scholar
disputed Diogenes, and argued that the legend about his name being Aristocles originated in the Hellenistic age.[c]
Education
Apuleius informs us that Speusippus praised Plato's quickness of mind and modesty as a boy, and the "first fruits of his youth infused with hard work and love of study". Plato must have been instructed in grammar, music, and gymnastics by the most distinguished teachers of his time. Dicaearchus went so far as to say that Plato wrestled at the Isthmian games. Plato had also attended courses of philosophy; before meeting Socrates, he first became acquainted with Cratylus (a disciple of Heraclitus, a prominent pre-Socratic Greek philosopher) and the Heraclitean doctrines.
Early Hebrew-language chronology works indicate that Plato met Jeremiah in Egypt and was thereby influenced by him. It is recorded that he initially perceived Jeremiah to be absurd.
Plato and Socrate
The precise relationship between Plato and Socrates remains an area of contention among scholars. Plato makes it clear in his Apology of Socrates, that he was a devoted young follower. In that dialogue, Socrates is presented as mentioning Plato by name as one of those youths close enough to him to have been corrupted, if he were in fact guilty of corrupting the youth, and questioning why their fathers and brothers did not step forward to testify against him if he was indeed guilty of such a crime (33d-34a). Later, Plato is mentioned along with Crito, Critobolus, and Apollodorus as offering to pay a fine of 30 minas on Socrates' behalf, in lieu of the death penalty proposed by Meletus (38b). In the Phaedo, the title character lists those who were in attendance at the prison on Socrates' last day, explaining Plato's absence by saying, "Plato was ill" (Phaedo 59b).
Plato never speaks in his own voice in his dialogues. In the Second Letter, it says, "no writing of Plato exists or ever will exist, but those now said to be his are those of a Socrates become beautiful and new" (341c); if the Letter is Plato's, the final qualification seems to call into question the dialogues' historical fidelity. In any case, Xenophon and Aristophanes seem to present a somewhat different portrait of Socrates than Plato paints. Some have called attention to the problem of taking Plato's Socrates to be his mouthpiece, given Socrates' reputation for irony and the dramatic nature of the dialogue form
Aristotle attributes a different doctrine with respect to the ideas to Plato and Socrates (Metaphysics 987b1–11). Putting it in a nutshell, Aristotle merely suggests that his idea of forms can be discovered through investigation of the natural world, unlike Plato's Forms that exist beyond and outside the ordinary range of human understanding.
Later life
Plato may have traveled in Italy, Sicily, Egypt and Cyrene. Said to have returned to Athens at the age of forty, Plato founded one of the earliest known organized schools in Western Civilization on a plot of land in the Grove of Hecademus or Academus. The Academy was "a large enclosure of ground that was once the property of a citizen at Athens named Academus (some, however, say that it received its name from an ancient hero). The Academy operated until it was destroyed by Lucius Cornelius Sulla in 84 BC. Neoplatonists revived the Academy in the early 5th century, and it operated until AD 529, when it was closed by Justinian I of Byzantium, who saw it as a threat to the propagation of Christianity. Many intellectuals were schooled in the Academy, the most prominent one being Aristotle.
Throughout his later life, Plato became entangled with the politics of the city of Syracuse. According to Diogenes Laertius, Plato initially visited Syracuse while it was under the rule of Dionysus. During this first trip Dionysus's brother-in-law, Dion of Syracuse, became one of Plato's disciples, but the tyrant himself turned against Plato. Plato was sold into slavery and almost faced death in Cyrene, a city at war with Athens, before an admirer bought Plato's freedom and sent him home. After Dionysius's death, according to Plato's Seventh Letter, Dion requested Plato return to Syracuse to tutor Dionysus II and guide him to become a philosopher king. Dionysius II seemed to accept Plato's teachings, but he became suspicious of Dion, his uncle. Dionysus expelled Dion and kept Plato against his will. Eventually Plato left Syracuse. Dion would return to overthrow Dionysus and ruled Syracuse for a short time before being usurped by Calippus, a fellow disciple of Plato.
Death
A variety of sources have given accounts of Plato's death. One story, based on a mutilated manuscript, suggests Plato died in his bed, whilst a young Thracian girl played the flute to him. Another tradition suggests Plato died at a wedding feast. The account is based on Diogenes Laertius's reference to an account by Hermippus, a third century Alexandrian. According to Tertullian, Plato simply died in his sleep.
Philosophy
Plato (left) and Aristotle (right), a detail of The School of Athens, a fresco by Raphael. Aristotle gestures to the earth, representing his belief in knowledge through empirical observation and experience, while holding a copy of his Nicomachean Ethics in his hand. Plato holds his Timaeus and gestures to the heavens, representing his belief in The Forms
Recurrent theme
Plato often discusses the father-son relationship and the "question" of whether a father's interest in his sons has much to do with how well his sons turn out. A boy in ancient Athens was socially located by his family identity, and Plato often refers to his characters in terms of their paternal and fraternal relationships. Socrates was not a family man, and saw himself as the son of his mother, who was apparently a midwife. A divine fatalist, Socrates mocks men who spent exorbitant fees on tutors and trainers for their sons, and repeatedly ventures the idea that good character is a gift from the gods. Crito reminds Socrates that orphans are at the mercy of chance, but Socrates is unconcerned. In the Theaetetus, he is found recruiting as a disciple a young man whose inheritance has been squandered. Socrates twice compares the relationship of the older man and his boy lover to the father-son relationship (Lysis 213a, Republic 3.403b), and in the Phaedo, Socrates' disciples, towards whom he displays more concern than his biological sons, say they will feel "fatherless" when he is gone.
In several dialogues, Socrates floats the idea that knowledge is a matter of recollection, and not of learning, observation, or study. He maintains this view somewhat at his own expense, because in many dialogues, Socrates complains of his forgetfulness. Socrates is often found arguing that knowledge is not empirical, and that it comes from divine insight. In many middle period dialogues, such as the Phaedo, Republic and Phaedrus Plato advocates a belief in the immortality of the soul, and several dialogues end with long speeches imagining the afterlife. More than one dialogue contrasts knowledge and opinion, perception and reality, nature and custom, and body and soul.
Several dialogues tackle questions about art: Socrates says that poetry is inspired by the muses, and is not rational. He speaks approvingly of this, and other forms of divine madness (drunkenness, eroticism, and dreaming) in the Phaedrus (265a–c), and yet in the Republic wants to outlaw Homer's great poetry, and laughter as well. In Ion, Socrates gives no hint of the disapproval of Homer that he expresses in the Republic. The dialogue Ion suggests that Homer's Iliad functioned in the ancient Greek world as the Bible does today in the modern Christian world: as divinely inspired literature that can provide moral guidance, if only it can be properly interpreted.
On politics and art, religion and science, justice and medicine, virtue and vice, crime and punishment, pleasure and pain, rhetoric and rhapsody, human nature and sexuality, love and wisdom, Socrates and his company of disputants had something to say.
Metaphysic
"Platonism" is a term coined by scholars to refer to the intellectual consequences of denying, as Socrates often does, the reality of the material world. In several dialogues, most notably the Republic, Socrates inverts the common man's intuition about what is knowable and what is real. While most people take the objects of their senses to be real if anything is, Socrates is contemptuous of people who think that something has to be graspable in the hands to be real. In the Theaetetus, he says such people are "eu a-mousoi", an expression that means literally, "happily without the muses" (Theaetetus 156a). In other words, such people live without the divine inspiration that gives him, and people like him, access to higher insights about reality.
Socrates's idea that reality is unavailable to those who use their senses is what puts him at odds with the common man, and with common sense. Socrates says that he who sees with his eyes is blind, and this idea is most famously captured in his allegory of the cave, and more explicitly in his description of the divided line. The allegory of the cave (begins Republic 7.514a) is a paradoxical analogy wherein Socrates argues that the invisible world is the most intelligible ("noeton") and that the visible world ("(h)oraton") is the least knowable, and the most obscure.
Socrates says in the Republic that people who take the sun-lit world of the senses to be good and real are living pitifully in a den of evil and ignorance. Socrates admits that few climb out of the den, or cave of ignorance, and those who do, not only have a terrible struggle to attain the heights, but when they go back down for a visit or to help other people up, they find themselves objects of scorn and ridicule.
According to Socrates, physical objects and physical events are "shadows" of their ideal or perfect forms, and exist only to the extent that they instantiate the perfect versions of themselves. Just as shadows are temporary, inconsequential epiphenomena produced by physical objects, physical objects are themselves fleeting phenomena caused by more substantial causes, the ideals of which they are mere instances. For example, Socrates thinks that perfect justice exists (although it is not clear where) and his own trial would be a cheap copy of it.
The allegory of the cave (often said by scholars to represent Plato's own epistemology and metaphysics) is intimately connected to his political ideology (often said to also be Plato's own), that only people who have climbed out of the cave and cast their eyes on a vision of goodness are fit to rule. Socrates claims that the enlightened men of society must be forced from their divine contemplations and be compelled to run the city according to their lofty insights. Thus is born the idea of the "philosopher-king", the wise person who accepts the power thrust upon him by the people who are wise enough to choose a good master. This is the main thesis of Socrates in the Republic, that the most wisdom the masses can muster is the wise choice of a ruler.
The word metaphysics derives from the fact that Aristotle's musings about divine reality came after ("meta") his lecture notes on his treatise on nature ("physics"). The term is in fact applied to Aristotle's own teacher, and Plato's "metaphysics" is understood as Socrates' division of reality into the warring and irreconcilable domains of the material and the spiritual. The theory has been of incalculable influence in the history of Western philosophy and religion.
Theory of Form
Main article: Theory of Form
The Theory of Forms (Greek: ἰδέαι) typically refers to the belief expressed by Socrates in some of Plato's dialogues, that the material world as it seems to us is not the real world, but only an image or copy of the real world. Socrates spoke of forms in formulating a solution to the problem of universals. The forms, according to Socrates, are roughly speaking archetypes or abstract representations of the many types of things, and properties we feel and see around us, that can only be perceived by reason (Greek: λογική); (that is, they are universals). In other words, Socrates sometimes seems to recognise two worlds: the apparent world, which constantly changes, and an unchanging and unseen world of forms, which may be a cause of what is apparent.
Epistemology
Many have interpreted Plato as stating that knowledge is justified true belief, an influential view that informed future developments in modern analytic epistemology. This interpretation is based on a reading of the Theaetetus wherein Plato argues that belief is to be distinguished from knowledge on account of justification. Many years later, Edmund Gettier famously demonstrated the problems of the justified true belief account of knowledge. This interpretation, however, imports modern analytic and empiricist categories onto Plato himself and is better read on its own terms than as Plato's view.
Really, in the Sophist, Statesman, Republic, and the Parmenides Plato himself associates knowledge with the apprehension of unchanging Forms and their relationships to one another (which he calls "expertise" in Dialectic). More explicitly, Plato himself argues in the Timaeus that knowledge is always proportionate to the realm from which it is gained. In other words, if one derives one's account of something experientially, because the world of sense is in flux, the views therein attained will be mere opinions. And opinions are characterized by a lack of necessity and stability. On the other hand, if one derives one's account of something by way of the non-sensible forms, because these forms are unchanging, so too is the account derived from them. It is only in this sense that Plato uses the term "knowledge".
In the Meno, Socrates uses a geometrical example to expound Plato's view that knowledge in this latter sense is acquired by recollection. Socrates elicits a fact concerning a geometrical construction from a slave boy, who could not have otherwise known the fact (due to the slave boy's lack of education). The knowledge must be present, Socrates concludes, in an eternal, non-experiential form.
The state
Papirus Oxyrhynchus, with fragment of Plato's Republic
Plato's philosophical views had many societal implications, especially on the idea of an ideal state or government. There is some discrepancy between his early and later views. Some of the most famous doctrines are contained in the Republic during his middle period, as well as in the Laws and the Statesman. However, because Plato wrote dialogues, it is assumed that Socrates is often speaking for Plato. This assumption may not be true in all cases.
Plato, through the words of Socrates, asserts that societies have a tripartite class structure corresponding to the appetite/spirit/reason structure of the individual soul. The appetite/spirit/reason stand for different parts of the body. The body parts symbolize the castes of society.
Productive, which represents the abdomen. (Workers) — the labourers, carpenters, plumbers, masons, merchants, farmers, ranchers, etc. These correspond to the "appetite" part of the soul.
Protective, which represents the chest. (Warriors or Guardians) — those who are adventurous, strong and brave; in the armed forces. These correspond to the "spirit" part of the soul.
Governing, which represents the head. (Rulers or Philosopher Kings) — those who are intelligent, rational, self-controlled, in love with wisdom, well suited to make decisions for the community. These correspond to the "reason" part of the soul and are very few.
According to this model, the principles of Athenian democracy (as it existed in his day) are rejected as only a few are fit to rule. Instead of rhetoric and persuasion, Plato says reason and wisdom should govern. As Plato puts it:
"Until philosophers rule as kings or those who are now called kings and leading men genuinely and adequately philosophise, that is, until political power and philosophy entirely coincide, while the many natures who at present pursue either one exclusively are forcibly prevented from doing so, cities will have no rest from evils,... nor, I think, will the human race." (Republic 473c-d)
Plato describes these "philosopher kings" as "those who love the sight of truth" (Republic 475c) and supports the idea with the analogy of a captain and his ship or a doctor and his medicine. According to him, sailing and health are not things that everyone is qualified to practice by nature. A large part of the Republic then addresses how the educational system should be set up to produce these philosopher kings.
However, it must be taken into account that the ideal city outlined in the Republic is qualified by Socrates as the ideal luxurious city, examined to determine how it is that injustice and justice grow in a city (Republic 372e). According to Socrates, the "true" and "healthy" city is instead the one first outlined in book II of the Republic, 369c–372d, containing farmers, craftsmen, merchants, and wage-earners, but lacking the guardian class of philosopher-kings as well as delicacies such as "perfumed oils, incense, prostitutes, and pastries", in addition to paintings, gold, ivory, couches, a multitude of occupations such as poets and hunters, and war.
In addition, the ideal city is used as an image to illuminate the state of one's soul, or the will, reason, and desires combined in the human body. Socrates is attempting to make an image of a rightly ordered human, and then later goes on to describe the different kinds of humans that can be observed, from tyrants to lovers of money in various kinds of cities. The ideal city is not promoted, but only used to magnify the different kinds of individual humans and the state of their soul. However, the philosopher king image was used by many after Plato to justify their personal political beliefs. The philosophic soul according to Socrates has reason, will, and desires united in virtuous harmony. A philosopher has the moderate love for wisdom and the courage to act according to wisdom. Wisdom is knowledge about the Good or the right relations between all that exists.
Wherein it concerns states and rulers, Plato has made interesting arguments. For instance he asks which is better—a bad democracy or a country reigned by a tyrant. He argues that it is better to be ruled by a bad tyrant, than be a bad democracy (since here all the people are now responsible for such actions, rather than one individual committing many bad deeds.) This is emphasised within the Republic as Plato describes the event of mutiny onboard a ship. Plato suggests the ships crew to be in line with the democratic rule of many and the captain, although inhibited through ailments, the tyrant. Plato's description of this event is parallel to that of democracy within the state and the inherent problems that arise.
According to Plato, a state made up of different kinds of souls will, overall, decline from an aristocracy (rule by the best) to a timocracy (rule by the honorable), then to an oligarchy (rule by the few), then to a democracy (rule by the people), and finally to tyranny (rule by one person, rule by a tyrant). Aristocracy is the form of government (politeia) advocated in Plato's Republic. This regime is ruled by a philosopher king, and thus is grounded on wisdom and reason. The aristocratic state, and the man whose nature corresponds to it, are the objects of Plato's analyses throughout much of the Republic, as opposed to the other four types of states/men, who are discussed later in his work. In Book VIII, Plato states in order the other four imperfect societies with a description of the state's structure and individual character. In timocracy the ruling class is made up primarily of those with a warrior-like character. In his description, Plato has Sparta in mind. Oligarchy is made up of a society in which wealth is the criterion of merit and the wealthy are in control. In democracy, the state bears resemblance to ancient Athens with traits such as equality of political opportunity and freedom for the individual to do as he likes. Democracy then degenerates into tyranny from the conflict of rich and poor. It is characterized by an undisciplined society existing in chaos, where the tyrant rises as popular champion leading to the formation of his private army and the growth of oppression.
Unwritten doctrine
For a long time Plato's unwritten doctrine had been controversial. Many modern books on Plato seem to diminish its importance; nevertheless the first important witness who mentions its existence is Aristotle, who in his Physics (209 b) writes: "It is true, indeed, that the account he gives there [i.e. in Timaeus] of the participant is different from what he says in his so-called unwritten teachings (ἄγραφα δόγματα)." The term ἄγραφα δόγματα literally means unwritten doctrines and it stands for the most fundamental metaphysical teaching of Plato, which he disclosed only orally, and some say only to his most trusted fellows, and which he may have kept secret from the public. The importance of the unwritten doctrines does not seem to have been seriously questioned before the 19th century.
A reason for not revealing it to everyone is partially discussed in Phaedrus (276 c) where Plato criticizes the written transmission of knowledge as faulty, favoring instead the spoken logos: "he who has knowledge of the just and the good and beautiful... will not, when in earnest, write them in ink, sowing them through a pen with words, which cannot defend themselves by argument and cannot teach the truth effectually." The same argument is repeated in Plato's Seventh Letter (344 c): "every serious man in dealing with really serious subjects carefully avoids writing." In the same letter he writes (341 c): "I can certainly declare concerning all these writers who claim to know the subjects that I seriously study... there does not exist, nor will there ever exist, any treatise of mine dealing therewith." Such secrecy is necessary in order not "to expose them to unseemly and degrading treatment" (344 d).
It is however said that Plato once disclosed this knowledge to the public in his lecture On the Good (Περὶ τἀγαθοῦ), in which the Good (τὸ ἀγαθόν) is identified with the One (the Unity, τὸ ἕν), the fundamental ontological principle. The content of this lecture has been transmitted by several witnesses, among others Aristoxenus who describes the event in the following words: "Each came expecting to learn something about the things that are generally considered good for men, such as wealth, good health, physical strength, and altogether a kind of wonderful happiness. But when the mathematical demonstrations came, including numbers, geometrical figures and astronomy, and finally the statement Good is One seemed to them, I imagine, utterly unexpected and strange; hence some belittled the matter, while others rejected it." Simplicius quotes Alexander of Aphrodisias who states that "according to Plato, the first principles of everything, including the Forms themselves are One and Indefinite Duality (ἡ ἀόριστος δυάς), which he called Large and Small (τὸ μέγα καὶ τὸ μικρόν)... one might also learn this from Speusippus and Xenocrates and the others who were present at Plato's lecture on the Good"
Their account is in full agreement with Aristotle's description of Plato's metaphysical doctrine. In Metaphysics he writes: "Now since the Forms are the causes of everything else, he [i.e. Plato] supposed that their elements are the elements of all things. Accordingly the material principle is the Great and Small [i.e. the Dyad], and the essence is the One (τὸ ἕν), since the numbers are derived from the Great and Small by participation in the One" (987 b). "From this account it is clear that he only employed two causes: that of the essence, and the material cause; for the Forms are the cause of the essence in everything else, and the One is the cause of it in the Forms. He also tells us what the material substrate is of which the Forms are predicated in the case of sensible things, and the One in that of the Forms - that it is this the duality (the Dyad, ἡ δυάς), the Great and Small (τὸ μέγα καὶ τὸ μικρόν). Further, he assigned to these two elements respectively the causation of good and of evil" (988 a).
The most important aspect of this interpretation of Plato's metaphysics is the continuity between his teaching and the neoplatonic interpretation of Plotinus or Ficino which has been considered erroneous by many but may in fact have been directly influenced by oral transmission of Plato's doctrine. A modern scholar who recognized the importance of the unwritten doctrine of Plato was Heinrich Gomperz who described it in his speech during the 7th International Congress of Philosophy in 1930. All the sources related to the ἄγραφα δόγματα have been collected by Konrad Gaiser and published as Testimonia Platonica. These sources have subsequently been interpreted by scholars from the German Tübingen School such as Hans Joachim Krämer or Thomas A. Szlezák.
Dialectic
The role of dialectic in Plato's thought is contested but there are two main interpretations; a type of reasoning and a method of intuition. Simon Blackburn adopts the first, saying that Plato's dialectic is “the process of eliciting the truth by means of questions aimed at opening out what is already implicitly known, or at exposing the contradictions and muddles of an opponent’s position.” Karl Popper, on the other hand, claims that dialectic is the art of intuition for "visualising the divine originals, the Forms or Ideas, of unveiling the Great Mystery behind the common man's everyday world of appearances."
Work
Thirty-six dialogues and thirteen letters have traditionally been ascribed to Plato, though modern scholarship doubts the authenticity of at least some of these. Plato's writings have been published in several fashions; this has led to several conventions regarding the naming and referencing of Plato's texts.
The usual system for making unique references to sections of the text by Plato derives from a 16th century edition of Plato's works by Henricus Stephanus. An overview of Plato's writings according to this system can be found in the Stephanus pagination article.
One tradition regarding the arrangement of Plato's texts is according to tetralogies. This scheme is ascribed by Diogenes Laertius to an ancient scholar and court astrologer to Tiberius named Thrasyllus.
In the list below, works by Plato are marked (1) if there is no consensus among scholars as to whether Plato is the author, and (2) if most scholars agree that Plato is not the author of the work. Unmarked works are assumed to have been written by Plato.
I. Euthyphro, (The) Apology (of Socrates), Crito, Phaedo
II. Cratylus, Theaetetus, Sophist, Statesman
III. Parmenides, Philebus, (The) Symposium, Phaedru
IV. First Alcibiades (1), Second Alcibiades (2), Hipparchus (2), (The) (Rival) Lovers (2)
V. Theages (2), Charmides, Laches, Lysi
VI. Euthydemus, Protagoras, Gorgias, Meno
VII. (Greater) Hippias (major) (1), (Lesser) Hippias (minor), Ion, Menexenu
VIII. Clitophon (1), (The) Republic, Timaeus, Critia
IX. Minos (2), (The) Laws, Epinomis (2), Epistles (1).
Sisyphus – Theage
The remaining works were transmitted under Plato's name, most of them already considered spurious in antiquity, and so were not included by Thrasyllus in his tetralogical arrangement. These works are labelled as Notheuomenoi ("spurious") or Apocrypha.
Axiochus (2), Definitions (2), Demodocus (2), Epigrams (2), Eryxias (2), Halcyon (2), On Justice (2), On Virtue (2), Sisyphus (2).
Composition of the dialogue
No one knows the exact order Plato's dialogues were written in, nor the extent to which some might have been later revised and rewritten.
Lewis Campbell was the first to make exhaustive use of stylometry to prove objectively that the Critias, Timaeus, Laws, Philebus, Sophist, and Statesman were all clustered together as a group, while the Parmenides, Phaedrus, Republic, and Theaetetus belong to a separate group, which must be earlier (given Aristotle's statement in his Politics that the Laws was written after the Republic; cf. Diogenes Laertius Lives 3.37). What is remarkable about Campbell's conclusions is that, in spite of all the stylometric studies that have been conducted since his time, perhaps the only chronological fact about Plato's works that can now be said to be proven by stylometry is the fact that Critias, Timaeus, Laws, Philebus, Sophist, and Statesman are the latest of Plato's dialogues, the others earlier.
Increasingly in the most recent Plato scholarship, writers are skeptical of the notion that the order of Plato's writings can be established with any precision, though Plato's works are still often characterized as falling at least roughly into three groups. The following represents one relatively common such division. It should, however, be kept in mind that many of the positions in the ordering are still highly disputed, and also that the very notion that Plato's dialogues can or should be "ordered" is by no means universally accepted.
Among those who classify the dialogues into periods of composition, Socrates figures in all of the "early dialogues" and they are considered the most faithful representations of the historical Socrates.
They include The Apology of Socrates, Charmides, Crito, Euthyphro, Ion, Laches, Less Hippias, Lysis, Menexenus, and Protagoras (often considered one of the last of the "early dialogues"). Three dialogues are often considered "transitional" or "pre-middle": Euthydemus, Gorgias, and Meno.
Whereas those classified as "early dialogues" often conclude in aporia, the so-called "middle dialogues" provide more clearly stated positive teachings that are often ascribed to Plato such as the theory of forms.
These dialogues include Cratylus, Phaedo, Phaedrus, Republic, Symposium, Parmenides, and Theaetetus.
Proponents of dividing the dialogues into periods often consider the Parmenides and Theaetetus to come late in this period and be transitional to the next, as they seem to treat the theory of forms critically (Parmenides) or not at all (Theaetetus).
The remaining dialogues are classified as "late" and are generally agreed to be difficult and challenging pieces of philosophy.
This grouping is the only one proven by stylometric analysis. While looked to for Plato's "mature" answers to the questions posed by his earlier works, those answers are difficult to discern. Some scholars[who?] say that the theory of forms is absent from the late dialogues, its having been refuted in the Parmenides, but there isn't total consensus that the Parmenides actually refutes the theory of forms. The so-called "late dialogues" include Critias, Laws, Philebus, Sophist, Statesman, and Timaeus.
Narration of the dialogue
Plato never presents himself as a participant in any of the dialogues, and with the exception of the Apology, there is no suggestion that he heard any of the dialogues firsthand. Some dialogues have no narrator but have a pure "dramatic" form (examples: Meno, Gorgias, Phaedrus, Crito, Euthyphro), some dialogues are narrated by Socrates, wherein he speaks in first person (examples: Lysis, Charmides, Republic). One dialogue, Protagoras, begins in dramatic form but quickly proceeds to Socrates' narration of a conversation he had previously with the sophist for whom the dialogue is named; this narration continues uninterrupted till the dialogue's end.
Two dialogues Phaedo and Symposium also begin in dramatic form but then proceed to virtually uninterrupted narration by followers of Socrates. Phaedo, an account of Socrates' final conversation and hemlock drinking, is narrated by Phaedo to Echecrates in a foreign city not long after the execution took place. The Symposium is narrated by Apollodorus, a Socratic disciple, apparently to Glaucon. Apollodorus assures his listener that he is recounting the story, which took place when he himself was an infant, not from his own memory, but as remembered by Aristodemus, who told him the story years ago.
The Theaetetus is a peculiar case: a dialogue in dramatic form imbedded within another dialogue in dramatic form. In the beginning of the Theaetetus (142c-143b), Euclides says that he compiled the conversation from notes he took based on what Socrates told him of his conversation with the title character. The rest of the Theaetetus is presented as a "book" written in dramatic form and read by one of Euclides' slaves (143c). Some scholars take this as an indication that Plato had by this date wearied of the narrated form. With the exception of the Theaetetus, Plato gives no explicit indication as to how these orally transmitted conversations came to be written down.
Trial of Socrate
Main article: Trial of Socrate
The trial of Socrates is the central, unifying event of the great Platonic dialogues. Because of this, Plato's Apology is perhaps the most often read of the dialogues. In the Apology, Socrates tries to dismiss rumors that he is a sophist and defends himself against charges of disbelief in the gods and corruption of the young. Socrates insists that long-standing slander will be the real cause of his demise, and says the legal charges are essentially false. Socrates famously denies being wise, and explains how his life as a philosopher was launched by the Oracle at Delphi. He says that his quest to resolve the riddle of the oracle put him at odds with his fellow man, and that this is the reason he has been mistaken for a menace to the city-state of Athens.
If Plato's important dialogues do not refer to Socrates' execution explicitly, they allude to it, or use characters or themes that play a part in it. Five dialogues foreshadow the trial: In the Theaetetus (210d) and the Euthyphro (2a–b) Socrates tells people that he is about to face corruption charges. In the Meno (94e–95a), one of the men who brings legal charges against Socrates, Anytus, warns him about the trouble he may get into if he does not stop criticizing important people. In the Gorgias, Socrates says that his trial will be like a doctor prosecuted by a cook who asks a jury of children to choose between the doctor's bitter medicine and the cook's tasty treats (521e–522a). In the Republic (7.517e), Socrates explains why an enlightened man (presumably himself) will stumble in a courtroom situation. The Apology is Socrates' defense speech, and the Crito and Phaedo take place in prison after the conviction. In the Protagoras, Socrates is a guest at the home of Callias, son of Hipponicus, a man whom Socrates disparages in the Apology as having wasted a great amount of money on sophists' fees.
Unity and diversity of the dialogue
Two other important dialogues, the Symposium and the Phaedrus, are linked to the main storyline by characters. In the Apology (19b, c), Socrates says Aristophanes slandered him in a comic play, and blames him for causing his bad reputation, and ultimately, his death. In the Symposium, the two of them are drinking together with other friends. The character Phaedrus is linked to the main story line by character (Phaedrus is also a participant in the Symposium and the Protagoras) and by theme (the philosopher as divine emissary, etc.) The Protagoras is also strongly linked to the Symposium by characters: all of the formal speakers at the Symposium (with the exception of Aristophanes) are present at the home of Callias in that dialogue. Charmides and his guardian Critias are present for the discussion in the Protagoras. Examples of characters crossing between dialogues can be further multiplied. The Protagoras contains the largest gathering of Socratic associates.
In the dialogues Plato is most celebrated and admired for, Socrates is concerned with human and political virtue, has a distinctive personality, and friends and enemies who "travel" with him from dialogue to dialogue. This is not to say that Socrates is consistent: a man who is his friend in one dialogue may be an adversary or subject of his mockery in another. For example, Socrates praises the wisdom of Euthyphro many times in the Cratylus, but makes him look like a fool in the Euthyphro. He disparages sophists generally, and Prodicus specifically in the Apology, whom he also slyly jabs in the Cratylus for charging the hefty fee of fifty drachmas for a course on language and grammar. However, Socrates tells Theaetetus in his namesake dialogue that he admires Prodicus and has directed many pupils to him. Socrates' ideas are also not consistent within or between or among dialogues.
Platonic scholarship
"The safest general characterisation of the European philosophical tradition is that it consists of a series of footnotes to Plato." (Alfred North Whitehead, Process and Reality, 1929).
Although their popularity has fluctuated over the years, the works of Plato have never been without readers since the time they were written. Plato's thought is often compared with that of his most famous student, Aristotle, whose reputation during the Western Middle Ages so completely eclipsed that of Plato that the Scholastic philosophers referred to Aristotle as "the Philosopher". However, in the Byzantine Empire, the study of Plato continued.
The Medieval scholastic philosophers did not have access to the works of Plato, nor the knowledge of Greek needed to read them. Plato's original writings were essentially lost to Western civilization until they were brought from Constantinople in the century of its fall, by George Gemistos Plethon. It is believed that Plethon passed a copy of the Dialogues to Cosimo de' Medici when in 1438 the Council of Ferrara, called to unify the Greek and Latin Churches, was adjourned to Florence, where Plethon then lectured on the relation and differences of Plato and Aristotle, and fired Cosimo with his enthusiasm.
Medieval scholars knew of Plato only through translations into Latin from the translations into Arabic by Persian and Arab scholars. These scholars not only translated the texts of the ancients, but expanded them by writing extensive commentaries and interpretations on Plato's and Aristotle's works (see Al-Farabi, Avicenna, Averroes).
Only in the Renaissance, with the general resurgence of interest in classical civilization, did knowledge of Plato's philosophy become widespread again in the West. Many of the greatest early modern scientists and artists who broke with Scholasticism and fostered the flowering of the Renaissance, with the support of the Plato-inspired Lorenzo de Medici, saw Plato's philosophy as the basis for progress in the arts and sciences. By the 19th century, Plato's reputation was restored, and at least on par with Aristotle's.
Notable Western philosophers have continued to draw upon Plato's work since that time. Plato's influence has been especially strong in mathematics and the sciences. He helped to distinguish between pure and applied mathematics by widening the gap between "arithmetic", now called number theory and "logistic", now called arithmetic. He regarded logistic as appropriate for business men and men of war who "must learn the art of numbers or he will not know how to array his troops," while arithmetic was appropriate for philosophers "because he has to arise out of the sea of change and lay hold of true being." Plato's resurgence further inspired some of the greatest advances in logic since Aristotle, primarily through Gottlob Frege and his followers Kurt Gödel, Alonzo Church, and Alfred Tarski; the last of these summarised his approach by reversing the customary paraphrase of Aristotle's famous declaration of sedition from the Academy (Nicomachean Ethics 1096a15), from Amicus Plato sed magis amica veritas ("Plato is a friend, but truth is a greater friend") to Inimicus Plato sed magis inimica falsitas ("Plato is an enemy, but falsehood is a greater enemy"). Albert Einstein drew on Plato's understanding of an immutable reality that underlies the flux of appearances for his objections to the probabilistic picture of the physical universe propounded by Niels Bohr in his interpretation of quantum mechanics.
Conversely, thinkers that diverged from ontological models and moral ideals in their own philosophy, have tended to disparage Platonism from more or less informed perspectives. Thus Friedrich Nietzsche attacked Plato's moral and political theories, Martin Heidegger argued against Plato's alleged obfuscation of Being, and Karl Popper argued in The Open Society and Its Enemies (1945) that Plato's alleged proposal for a government system in the Republic was prototypically totalitarian. Leo Strauss is considered by some as the prime thinker involved in the recovery of Platonic thought in its more political, and less metaphysical, form. Deeply influenced by Nietzsche and Heidegger, Strauss nonetheless rejects their condemnation of Plato and looks to the dialogues for a solution to what all three thinkers acknowledge as 'the crisis of the West.'
Textual sources and history
The texts of Plato as received today apparently represent the complete written philosophical work of Plato and are generally good by the standards of textual criticism. No modern edition of Plato in the original Greek represents a single source, but rather it is reconstructed from multiple sources which are compared with each other. These sources are medieval manuscripts written on vellum (mainly from 9th-13th century AD Byzantium), papyri (mainly from late antiquity in Egypt), and from the independent testimonia of other authors who quote various segments of the works (which come from a variety of sources). The text as presented is usually not much different than what appears in the Byzantine manuscripts, and papyri and testimonia just confirm the manuscript tradition. In some editions however the readings in the papyri or testimonia are favoured in some places by the editing critic of the text.
In the first century AD, Thrasyllus of Mendes had compiled and published the works of Plato in the original Greek, both genuine and spurious. While it has not survived to the present day, all the extant medieval Greek manuscripts are based on his edition.
The oldest surviving complete manuscript for many of the dialogues is the Clarke Plato (Codex Oxoniensis Clarkianus 39, or Codex Boleianus MS E.D. Clarke 39), which was written in Constantinople in 895 and acquired by Oxford University in 1809. The Clarke is given the siglum B in modern editions. B contains the first six tetralogies and is described internally as being written by "John the Calligrapher" on behalf of Arethas of Caesarea. It appears to have undergone corrections by Arethas himself. For the last two tetralogies and the apocrypha, the oldest surviving complete manuscript is Codex Parisinus graecus 1807, designated A, which was written nearly contemporaneously to B, circa 900 AD. A probably had an initial volume containing the first 7 tetralogies which is now lost, but of which a copy was made, Codex Venetus append. class. 4, 1, which has the siglum T. The oldest manuscript for the seventh tetralogy is Codex Vindobonensis 54. suppl. phil. Gr. 7, with siglum W, with a supposed date in the twelfth century. In total there are fifty-one such Byzantine manuscripts known, while others may yet be found.
To help establish the text, the older evidence of papyri and the independent evidence of the testimony of commentators and other authors (i.e, those who quote and refer to an old text of Plato which is so longer extant) are also used. Many papyri which contain fragments of Plato's texts are among the Oxyrhynchus Papyri. The 2003 Oxford Classical Texts edition by Slings even cites the Coptic translation of a fragment of the Republic in the Nag Hammadi library as evidence. Important authors for testimony include Olympiodorus the Younger, Plutarch, Proclus, Iamblichus, Eusebius, and Stobaeus.
During the early Renaissance, the Greek language and, along with it, Plato's texts were reintroduced to Western Europe by Byzantine scholars. In 1483 there was published a Latin edition of Plato's complete works translated by Marsilio Ficino at the behest of Cosimo de' Medici. Cosimo had been influenced toward studying Plato by the many Byzantine Platonists in Florence during his day, including George Gemistus Plethon. Henri Estienne's edition, including parallel Greek and Latin, was published in 1578. It was this edition which established Stephanus pagination, still in use today.
Modern edition
The Oxford Classical Texts offers the current standard complete Greek text of Plato's complete works. In five volumes edited by John Burnet, its first edition was published 1900-1907, and it is still available from the publisher, having last been printed in 1993. The second edition is still in progress with only the first volume, printed in 1995, and the Republic, printed in 2003, available. The Cambridge Greek and Latin Texts and Cambridge Classical Texts and Commentaries series includes Greek editions of the Protagoras, Symposium, Phaedrus, Alcibiades, and Clitophon, with English philological, literary, and, to an extent, philosophical commentary. One distinguished edition of the Greek text is E. R. Dodds' of the Gorgias, which includes extensive English commentary.
The modern standard complete English edition is the 1997 Hackett Plato, Complete Works, edited by John M. Cooper. For many of these translations Hackett offers separate volumes which include more by way of commentary, notes, and introductory material. There is also the Clarendon Plato Series by Oxford University Press which offers English translations and thorough philosophical commentary by leading scholars on a few of Plato's works, including John McDowell's version of the Theaetetus. Cornell University Press has also begun the Agora series of English translations of classical and medieval philosophical texts, including a few of Plato's.
Criticism
Carl Sagan said of Plato: "Science and mathematics were to be removed from the hands of the merchants and the artisans. This tendency found its most effective advocate in a follower of Pythagoras named Plato." and: "He (Plato) believed that ideas were far more real than the natural world. He advised the astronomers not to waste their time observing the stars and planets. It was better, he believed, just to think about them. Plato expressed hostility to observation and experiment. He taught contempt for the real world and disdain for the practical application of scientific knowledge. Plato's followers succeeded in extinguishing the light of science and experiment that had been kindled by Democritus and the other Ionians."