| 帕拉图 | |||
| 阿里斯托勒斯 | |||
阅读柏拉图 Plato在诗海的作品!!! | |||
也译为帕拉图
拼音：Bó lā tú
英译：Plato
希腊语：Πλάτων
(约公元前427年－前347年）
古希腊哲学家，也是全部西方哲学乃至整个西方文化最伟大的哲学家和思想家之一，他和老师苏格拉底，学生亚里士多德并称为古希腊三大哲学家。
【简介】
名字的由来：柏拉图原名阿里斯托勒斯，却又何以改称“柏拉图”？溯其源，阿里斯托勒斯自幼身体强壮，胸宽肩阔。因此体育老师就替他取了“柏拉图”一名，“柏拉图”希腊语意为“宽阔”。后来，柏拉图的名字被延用下来，流行至今。
柏拉图出身于雅典贵族，青年时从师苏格拉底。苏氏死后，他游历四方，曾到埃及、小亚细亚和意大利南部从事政治活动，企图实现他的贵族政治理想。公元前387年活动失败后逃回雅典，在一所称为阿加德米（Academy）的体育馆附近设立了一所学园，此后执教40年，直至逝世。他一生著述颇丰，其教学思想主要集中在《理想国》（The Republic）和《法律篇》中。
柏拉图是西方客观唯心主义的创始人，其哲学体系博大精深，对其教学思想影响尤甚。柏拉图认为世界由“理念世界”和“现象世界”所组成。理念的世界是真实的存在，永恒不变，而人类感官所接触到的这个现实的世界，只不过是理念世界的微弱的影子，它由现象所组成，而每种现象是因时空等因素而表现出暂时变动等特征。由此出发，柏拉图提出了一种理念论和回忆说的认识论，并将它作为其教学理论的哲学基础。
柏拉图认为人的一切知识都是由天赋而来，它以潜在的方式存在于人的灵魂之中。因此认识不是对世界物质的感受，而是对理念世界的回忆。教学目的是为了恢复人的固有知识。教学过程即是"回忆"理念的过程。在教学中，柏拉图重视对普遍、一般的认识，特别重视学生思维能力的培养，认为概念、真理是纯思维的产物。同时他又认为学生是通过理念世界在现象世界的影子中才得以回忆起理念世界的，承认感觉在认识中的刺激作用。他特别强调早期教育和环境对儿童的作用。认为在幼年时期儿童所接触到的事物对他有着永久的影响，教学过程要通过具体事物的感性启发，引起学生的回忆，经过反省和思维，再现出灵魂中固有的理念知识。就此而言，柏拉图的教学认识是一种先验论。
柏拉图的教学体系是金字塔形。为了发展理性，他设立了全面而丰富的课程体系，他以学生的心理特点为依据，划分了几个年龄阶段，并分别授以不同的教学科目。0一3岁的幼儿在育儿所里受到照顾。3一6岁的儿童在游乐场内进行故事、游戏、唱歌等活动。6岁以后，儿童进入初等学校接受初级课程。在教学内容上，柏拉图接受了雅典以体操锻炼身体，以音乐陶冶心灵的和谐发展的教育思想，为儿童安排了简单的读、写、算、唱歌，同时还十分重视体操等体育训练项目。17一20岁的青年升入国立的“埃弗比” 接受军事教育，并结合军事需要学习文化科目，主要有算术、几何、天文、音乐。20一30岁，经过严格挑选，进行10年科学教育，着重发展青年的思维能力，继续学习"四科"，懂得自然科学间的联系。30岁以后，经过进一步挑选，学习5年，主要研究哲学等。至此，形成了柏拉图相对完整的金字塔形的教学体系。
根据其教学目的，柏氏吸收和发展了智者的‘三艺’及斯巴达的军事体育课程，也总结了雅典的教学实践经验，在教育史上第一次提出了“四科”（算术、几何、天文、音乐），其后便成了古希腊课程体系的主干和导源，支配了欧洲的中等与高等教育达1500年之久。
柏拉图认为，每门学科均有其独特的功能，凡有所学，皆会促成性格的发展。在17岁之前，广泛而全面的学科内容是为了培养公民的一般素养，而对于未来的哲学家来讲，前面所述的各门学科都是学习辩证法必不可少的知识准备。文法和修辞是研究哲学的基础；算术是为了锻炼人的分析与思考能力：学习几何、天文，对于航海、行军作战、观测气候、探索宇宙十分重要；学习音乐则是为了培养军人的勇敢和高尚的道德情操。同时，他还很重视选择和净化各种教材，如语言、故事、神话、史诗等，使其符合道德要求，以促进儿童心智之发展。
就教学方法而言，柏拉图师承苏格拉底的问答法，把回忆已有知识的过程视为一种教学和启发的过程。他反对用强制性手段灌输知识，提倡通过问答形式，提出问题，揭露矛盾，然后进行分析、归纳、综合、判断，最后得出结论。
理性的训练是柏拉图教学思想的主要特色。在教学过程中，柏拉图始终是以发展学生的思维能力为最终目标的。在《理想国》中，他多次使用了“反思”（reflection）和“沉思”（contemplation）两词，认为关于理性的知识唯有凭借反思、沉思才能真正融会贯通，达到举一反三。感觉的作用只限于现象的理解，并不能成为获得理念的工具。因此，教师必须引导学生心思凝聚，学思结合，从一个理念到达另一个理念，并最终归给为理念。教师要善于点悟、启发、诱导学生进入这种境界，使他们在“苦思冥想”后“顿开茅塞”，喜获“理性之乐”。这与苏格拉底的助产术有异曲同工之妙。
柏拉图的教学思想几乎涉及到教学领域中的所有重要方法。他第一个确定了心理学的基本划分，并使之与教学密切联系起来。他继承并发展了斯巴达的依据年龄特征划分教学阶段的教学理论，在教学的具体内容、形式、方法和手段上则更多地总结与采用了雅典的经验，提出了全面、和谐发展的课程体系。他十分注重在教学中发展学生的思维能力，强调探讨事物的本质，这些都给了后世教育家们以巨大的影响和启迪。
但是，柏拉图夸大了理性发展在教学中的意义。他主张的通过回忆和沉思冥想以致知的教学过程，反映了其对掌握知识理解中的唯心主义倾向。特别是他把理性绝对化、孤立化，使感觉和理性之间对立起来的思想，以致成了中世纪经院派教条主义教学方法的理论基础。他有一句名言：不知道自己的无知，乃是双倍的无知。
【生平】
一般推测柏拉图出生的年份应该是在公元前427年或前428年的5月或12月（如同其他早期的西方哲学家，他的出生日期也依然未知）。柏拉图生于一个较为富裕的贵族家庭，他的父亲是阿里斯通（Ariston）、母亲是克里提俄涅（Perictione），他在家中排行老四。他的家庭宣称是古雅典国王的后代，他也是当时雅典知名的政治家柯里西亚斯（Critias）的侄子，不过两人之间的关系也仍有争议。依据后来第欧根尼·拉尔修的说法，柏拉图的原名为亚里斯多克勒斯（Aristokles），后来因为他强壮的身躯而被称为柏拉图（在希腊语中，Platus一词是“平坦、宽阔”等意思）。但第欧根尼也提起了其他的说法，柏拉图这个名字也可能是来自他流畅宽广（platutês）的口才、或因为他拥有宽广的前额。由于柏拉图出色的学习能力和其他才华，古希腊人还称赞他为阿波罗之子，并称在柏拉图还是婴儿的时候曾有蜜蜂停留在他的嘴唇上，才会使他口才如此甜蜜流畅。
公元前399年，苏格拉底受审并被判死刑，柏拉图对现存的政体完全失望，于是开始游遍意大利、西西里岛、埃及、昔兰尼等地以寻求知识。在四十岁时（约公元前387年）他结束旅行返回雅典，并在雅典城外西北郊的圣城阿卡德米创立了自己的学校——阿卡德米学园（Academy），学院成为西方文明最早的有完整组织的高等学府之一，后世的高等学术机构也因此而得名，也是中世纪时在西方发展起来的大学的前身。 阿卡德米坐落于一处曾为希腊传奇英雄阿卡得摩斯（Academus）住所的土地上，因而以此命名。学院存在了900多年，直到公元529年被查士丁尼大帝关闭为止。学院受到毕达哥拉斯的影响很大，课程设置类似于毕达哥拉斯学派的传统课题，包括了算术、几何学、天文学以及声学。据说，柏拉图在学园门口立了块碑：“不懂几何者不准入内”。学院培养出了许多知识分子，其中最杰出的是亚里士多德。
除了荷马之外，柏拉图也受到许多那之前的作家和思想家的影响，包括了毕达哥拉斯所提出的“和谐”概念，以及阿那克萨哥拉教导苏格拉底应该将心灵或理性作为判断任何事情的根据；巴门尼德提出的连结所有事物的理论也可能影响了柏拉图对于灵魂的概念。
【年表】
一、 成长时期28年：
公元前427年 柏拉图出生（奥林匹克88届第一年），家世显赫，此年即伯罗奔尼撒战争爆发后4年，伯里克利死后第二年，苏格拉底42岁（是年西西里莱翁蒂尼（Leontini）邦人高尔吉亚来雅典求援，告叙拉古入侵其邦）。
公元前423年 4岁，阿里斯托芬《云》上演，苏格拉底在场观赏，当场现身示众，态度自若。
公元前421年 6岁，据说是《理想国》发生时间（或所托时间）。
公元前420年 7岁，进狄奥尼索斯学校，识字，听荷马等诗作。
公元前411年 16岁，普罗塔哥拉被400人大会中人指控使人不信神，逃出雅典，在往西西里途中遇难（前此哲学家受迫害或驱逐、处死、或自愿放逐的还有阿那克萨哥拉，毕达哥拉斯、赫拉克利特）。
公元前409-404年 估计到过骑兵执勤，据说参加过3次战役。
公元前408年 高尔吉亚在第93届奥林匹亚运动会上发表演说，呼吁雅典和斯巴达团结起来对付波斯。
公元前407年 20岁跟随苏格拉底学习，此前曾向克拉底鲁学习赫拉克利特哲学；向赫莫根尼学习巴门尼德哲学。据说曾想写戏剧，给苏格拉底看，被否定。
公元前405年 叙拉古狄奥尼索斯推翻民主，建立僭主政权。
公元前404年 23岁，伯罗奔尼撒战争结束，雅典30僭主，柏拉图一度想从政，后失望。
公元前399年 28岁，苏格拉底受审（柏拉图在场）并被处死，就死时因病不在（太伤心？）。
二、游学12年
公元前398年 柏拉图与其他苏格拉底的弟子纷纷离开雅典到外地避风，到过西西里、意大利、埃及。
公元前392年 35岁，在这前后，撰写早期对话：《申辩》、《克力同》、《游叙弗伦》、《拉齐斯》、《吕西斯》、《查米迪斯篇》。
伊索克拉底在雅典办学园，教演讲术。
公元前390年 出访：毕达哥拉斯学派掌握的政权等。
公元前388年 访叙拉古狄奥尼索斯一世，结识其小舅子（女婿）狄翁（时狄翁20岁），成为至交，（此其间据说曾得罪僭主被卖作奴隶，由安尼舍里斯赎身）。
三、讲学20年
公元前387年 40岁，回到雅典，开始个人讲学，或说此年建立学园，此前后撰写对话：《普罗塔哥拉》、《美诺》、《尤息德谟斯篇》。
又中期著作：《理想国》、《会饮》、《斐得若》、《费多》等最具戏剧性的对话。
公元前385年 （见陈表：苏格拉底案的平反：控告人的死，立苏格拉底雕像，但不一定真实。又陶行知1938到雅典参观石牢，坐5分钟以示敬仰，又写诗“这位老人家，为何也坐牢？欢喜说真话，假人都烦恼”，又杜汝辑、叶秀山文章谈及此）。
公元前384年 43岁，亚里士多德生，德谟斯提尼生。
公元前380年 大约在这些年，在雅典西北郊外的陶器区建立学园。“不懂几何学者勿入此门。
公元前376年 高尔吉亚死。
公元前371年 底比斯军在伊巴密浓达指挥下，大败斯巴达。
公元前370年 德谟克利特死，据说柏拉图曾想购其书付之一炬。
四、晚年最后的政治尝试及讲学、著述：20年（或可再分两段：政治、著述）
公元前367年 60岁，将学园交欧多克索主持，自己带弟子和友人第二次往叙拉古，当年老狄奥尼索斯死，狄翁摄政，此时柏拉图已声名远播希腊及以外
亚里士多德来雅典学习（据说讲善，仅剩亚里士多德一人听）
公元前366年 狄奥尼索斯二世继位，狄翁逃离，柏拉图怅然离开叙拉古。
公元前363年 64岁，第三次往叙拉古，被扣留，被逐。
公元前357年 70岁，放弃政治活动，全力著述，晚期著作有：智者、政治家、斐里布、蒂迈欧篇。
公元前356年 亚历山大大帝出生。
公元前348年 晚年最后的著作是：法律篇，伊璧诺米篇续篇，刚开篇即去世。
公元前347年 春季（三月？）去世，遗嘱对用于校舍的房产，不许出售、转让。留下四家奴，释放一奴隶，财产很少。
公元前344-343年 狄奥尼索斯二世最后被推翻，亚里士多德任亚历山大教师。
比较孔子（前551-479）：
15-30岁，初仕鲁，做小官，“工读”时期：15年
30-50岁，专一讲学期，34岁授徒讲学： 20年
51-54岁，再仕鲁，任司寇，从政期： 4年
55-68岁，周游列国时期： 14年
69-73岁，晚年整理古籍： 5年
【地位】
柏拉图与他的学生亚里士多德比起来，在西方得到更多的尊重和注意。因为他的作品是西方文化的奠基文献。在西方哲学的各个学派中，很难找到没有吸收过他的著作的学派。在后世哲学家和基督教神学中，柏拉图的思想保持着巨大的辐射力。有的哲学史家认为，直到近代，西方哲学才逐渐摆脱了柏拉图思想的控制。
公元12世纪以前，亚里士多德的学说一直被教廷排斥，甚至欧洲已经不再流传亚里士多德的著作。当时，柏拉图的学说占统治地位，因为圣奥古斯丁借用和改造了柏拉图的思想，以服务神学教义。直到13世纪，托马斯·阿奎那利用亚里士多德的学说解释宗教教义，建立了烦琐和庞大的经院哲学。亚里士多德才重新被重视。
柏拉图的理论，被1949年后的中华人民共和国官方认为是唯心主义的。但他对西方哲学的启蒙作用被普遍认可，也因为他卓越的人格而备受尊重。
【主要著作】
柏拉图才思敏捷，研究广泛，著述颇丰。以他的名义流传下来的著作有40多篇，另有13封书信。柏拉图的主要哲学思想都是通过对话的形式记载下来的。在柏拉图的对话中，有很多是以苏格拉底之名进行的谈话，因此人们很难区分哪些是苏格拉底的思想，哪些是柏拉图的思想。经过后世一代代学者艰苦细致的考证，其中有24篇和4封书信被确定为真品，主要有：
I《伊壁鸠鲁篇》《苏格拉底的申辩》 《克力同篇》 《斐多篇》
II《克堤拉斯篇》《泰阿泰德篇》《智士篇》 《政治家篇》
III《巴曼尼得斯篇》《菲力帕斯篇》 《飨宴篇》《斐德罗篇篇》
IV《阿奇拜得篇之一》《阿奇拜得篇之二》 《高尔吉亚篇》
《智者篇》《政治家篇》《斐利布斯篇》《法律篇》《理想国》
《苏格拉底的申辩》 《理想国》 《巴曼尼得斯篇》《苏格拉底之死》
柏拉图伪作也有重要的学术意义，以下著作被认为是后世伪托的作品：
《米诺斯》（Minos）《欧律克西亚斯》（Eryxias）《泰戈斯》（Theages）《克里托芬》（Cleitophon）《爱人》（Lovers）
柏拉图的著作大多是用对话体裁写成的，人物性格鲜明，场景生动有趣，语言优美华丽，论证严密细致，内容丰富深刻，达到了哲学与文学、逻辑与修辞的高度统一，不仅在哲学上而且在文学上亦具有极其重要的意义和价值。
目前使用广泛的是《柏拉图全集》（四卷本），人民出版社出版，王晓朝译。
【思想概述】
柏拉图认为任何一种哲学要能具有普遍性，必须包括一个关于自然和宇宙的学说在内。柏拉图试图掌握有关个人和大自然永恒不变的真理，因此发展一种适合并从属于他的政治见解和神学见解的自然哲学。
柏拉图认为，自然界中有形的东西是流动的，但是构成这些有形物质的“形式”或“理念”却是永恒不变的。柏拉图指出，当我们说到“马”时，我们没有指任何一匹马，而是称任何一种马。而“马”的含义本身独立于各种马（“有形的”），它不存在于空间和时间中，因此是永恒的。但是某一匹特定的、有形的、存在于感官世界的马，却是“流动”的，会死亡，会腐烂。这可以作为柏拉图的“理念论”的一个初步的解说。
柏拉图认为，我们对那些变换的、流动的事物不可能有真正的认识，我们对它们只有意见或看法，我们唯一能够真正了解的，只有那些我们能够运用我们的理智来了解的“形式”或者“理念”。因此柏拉图认为，知识是固定的和肯定的，不可能有错误的知识。但是意见是有可能错误的。
在柏拉图的《理想国》中，有一个著名的洞穴比喻来解释理念论：有一群囚犯在一个洞穴中，他们手脚都被捆绑，身体也无法转身，只能背对着洞口。他们面前有一堵白墙，他们身后燃烧着一堆火。在那面白墙上他们看到了自己以及身后到火堆之间事物的影子，由于他们看不到任何其他东西，这群囚犯会以为影子就是真实的东西。最后，一个人挣脱了枷锁，并且摸索出了洞口。他第一次看到了真实的事物。他返回洞穴并试图向其他人解释，那些影子其实只是虚幻的事物，并向他们指明光明的道路。但是对于那些囚犯来说，那个人似乎比他逃出去之前更加愚蠢，并向他宣称，除了墙上的影子之外，世界上没有其他东西了。
柏拉图利用这个故事来告诉我们，“形式”其实就是那阳光照耀下的实物，而我们的感官世界所能感受到的不过是那白墙上的影子而已。我们的大自然比起鲜明的理型世界来说，是黑暗而单调的。不懂哲学的人能看到的只是那些影子，而哲学家则在真理的阳光下看到外部事物。
柏拉图的《理想国》还向我们描绘出了一幅理想的乌托邦的画面，柏拉图认为，国家应当由哲学家来统治。柏拉图的理想国中的公民划分为卫国者、士兵和普通人民三个阶级。卫国者是少部分管理国家的精英。他们可以被继承，但是其他阶级的优秀儿童也可以被培养成卫国者，而卫国者中的后代也有可能被降到普通人民的阶级。卫国者的任务是监督法典的制定和执行情况。为达到该目的柏拉图有一整套完整的理论。他的理想国要求每一个人在社会上都有其特殊功能，以满足社会的整体需要。但是在这个国家中，女人和男人有着同样的权利，存在着完全的性平等。政府可以在为了公众利益时撒谎。每一个人应该去做自己份内的事而不应该打扰到别人。在今天看来，柏拉图描绘的理想国是一个可怕的极权主义国家。但是“理想国其实是用正确的方式管理国家的科学家的观点”，柏拉图本人并没有试图实现理想国中的国家机器。
柏拉图在《律法》(The Laws)则指出，“宪法国家”是仅次于理想国的最好的国家。他在该书中同样指出，妇女和男人应该得到同样的尊重和训练。
柏拉图企图使天文学成为数学的一个部门。他认为：“天文学和几何学一样，可以靠提出问题和解决问题来研究，而不去管天上的星界。”柏拉图认为宇宙开头是没有区别的一片混沌。这片混沌的开辟是一个超自然的神的活动的结果。依照柏拉图的说法，宇宙由混沌变得秩序井然，其最重要的特征就是造物主为世界制定了一个理性方案；关于这个方案付诸实施的机械过程，则是一种想当然的自然事件。
柏拉图的宇宙观基本上是一种数学的宇宙观。他设想宇宙开头有两种直角三角形，一种是正方形的一半，另一种是等边三角形的一半。从这些三角形就合理地产生出四种正多面体，这就组成四种元素的微粒。火微粒是正四面体，气微粒是正八面体，水微粒是正二十面体，土微粒是立方体。第五种正多面体是由正五边形形成的十二面体，这是组成天上物质的第五种元素，叫做以太。整个宇宙是一个圆球，因为圆球是对称和完善的，球面上的任何一点都是一样。宇宙也是活的，运动的，有一个灵魂充溢全部空间。宇宙的运动是一种环行运动，因为圆周运动是最完善的，不需要手或脚来推动。四大元素中每一种元素在宇宙内的数量是这样的：火对气的比例等于气对水的比例和水对土的比例。万物都可以用一个数目来定名，这个数目就是表现它们所含元素的比例。
【政治思想】
在《理想国》中，柏拉图设计了一幅正义之邦的图景：国家规模适中，以站在城中高处能将全国尽收眼底，国人彼此面识为度。柏拉图认为国家起源于劳动分工，因而他将理想国中的公民分为治国者、武士、劳动者3个等级，分别代表智慧、勇敢和欲望3种品性。治国者依靠自己的哲学智慧和道德力量统治国家;武士们辅助治国，用忠诚和勇敢保卫国家的安全；劳动者则为全国提供物质生活资料。3个等级各司其职，各安其位。在这样的国家中，治国者均是德高望重的哲学家，只有哲学家才能认识理念，具有完美的德行和高超的智慧，明了正义之所在，按理性的指引去公正地治理国家。治国者和武士没有私产和家庭，因为私产和家庭是一切私心邪念的根源。劳动者也绝不允许拥有奢华的物品。理想国还很重视教育，因为国民素质与品德的优劣决定国家的好坏。柏拉图甚至设想在建国之初就把所有10岁以上的人遣送出国，因为他们已受到旧文化的熏染，难以改变。全体公民从儿童时代开始就要接受音乐、体育、数学到哲学的终身教育。教育内容要经严格选择，荷马、赫西俄德的史诗以及悲剧诗人们的作品，一律不准传入国境，因为它们会毒害青年的心灵。柏拉图自称这是“第一等好”的理想国，其他的政体都是这一理想政体的蜕变。理想政体由于婚配的不善引起3个等级的混杂，导致争斗，军人政体（Timocracy）随之兴起。军人政体中， 少数握有权势者聚敛财富，形成寡头政体（Oligarchy）。贫富矛盾的尖锐化导致民众的革命，产生民主政体（Democracy）。民主政体发展到极端时又会被僭主政体（Tyranny）所取代。
《政治家篇》约作于柏拉图后两次去叙拉古之间（公元前367～前361），这是他在叙拉古的政治实践受到挫折，思想发生变化的时期。《政治家篇》主旨是讨论真政治家及政治的定义。柏拉图在这篇对话中提出了政治中道、混合的概念；首次明确论述了法律的作用并以法律作为划分政体的标准。他认为，真政治家（哲学王）无需用法律统治，但现实中真政治家极为罕见，即使有真政治家，法律也还有一定的作用。因为政治不仅是一种艺术，亦是一门科学。法律对于政治家，犹如教练和医生的训练方案和处方一样，法律虽然在理论上是荒谬的，在实践中却是必要的。
柏拉图在其最后的作品《法律篇》中进一步发挥了关于法律的作用的思想。从理想出发，他推崇哲学王的统治，“没有任何法律或条例比知识更有威力”；从现实出发，他强调人类必须有法律并且遵守法律，否则他们的生活将如同最野蛮的兽类。在这一思想指导下，他在12卷的《法律篇》中，设计了他的“第二等好”的城邦，包括地理环境、疆域大小、人口规模与来源、国家经济生活、阶级结构、政治制度、法律等细则。由于指导思想的变化，第二等好的城邦与《理想国》中的正义之邦相比，在具体措施上有很大区别。主要有：政治制度由哲学王执政的贤人政体转为混合政体，以防止个人专权。《理想国》主张统治者实行公产、公妻、公餐、公育制，《法律篇》则恢复了私有财产和家庭。《理想国》中划分公民等级是依照其先天禀赋的优劣，而《法律篇》则是按照后天财产的多寡。
【教育观】
柏拉图还是西方教育史上第一个提出完整的学前教育思想并建立了完整的教育体系的人。柏拉图中年开始从事教育研究活动。他从理念先于物质而存在的哲学思想出发，在其教育体系中强调理性的锻炼。他要求3～6岁的儿童都要受到保姆的监护，会集在村庄的神庙里，进行游戏、听故事和童话。柏拉图认为这些都具有很大的教育意义。7岁以后，儿童就要开始学习军人所需的各种知识和技能，包括读、写、算、骑马、投枪、射箭等等。从20～30岁，那些对抽象思维表现特殊兴趣的学生就要继续深造，学习算术、几何、天文学与和声学等学科，以锻炼他的思考能力，使他开始探索宇宙的奥妙。柏拉图指出了每门学科对于发展抽象思维的意义。他主张未来的统治者在30岁以后，要进一步学习辩证法，以洞察理念世界。经过5年后，他就可以成为统治国家的哲学王了。
在他的奴隶主教育学体系中，体育占有重要的地位。柏拉图对妇女体育也很重视。他认为：“做女孩的应该练习各种跳舞和角力；结婚以后，便要参加战斗演习、行营布阵和使用武器……因为一旦当所有的军队出动去打敌人的时候，她们就能保卫儿童和城市” （《柏拉图论教育》）。在柏拉图的论述中，几乎涉及到当时体育的各个方面。他认为，体育应包括教育手段和健康术。他对当时雅典出现的竞技主义和竞技职业化倾向曾给予猛烈的抨击，同时也批评市民轻视体育的思想和态度。他主张心身和谐发展，强调“用体育锻炼身体，用音乐陶冶心灵”。柏拉图丰富的体育思想对后世体育的发展有深远的影响。
【爱情观】
柏拉图和亚里士多德是古希腊哲学家中最有影响的人，而在他们两个人中间，柏拉图对于后代所起的影响尤其来得大。柏拉图著书以他的老师苏格拉底之口表述说，当心灵摒绝肉体而向往着真理的时候，这时的思想才是最好的。而当灵魂被肉体的罪恶所感染时，人们追求真理的愿望就不会得到满足。
在欧洲，很早就有被我们中国人称之为“精神恋爱”的柏拉图式的爱，这种爱认为肉体的结合是不纯洁的是肮脏的，认为爱情和情欲是互相对立的两种状态，因此，当一个人确实在爱着的时候，他完全不可能想到要在肉体上同他所爱的对象结合。
在今天的人们看来，柏拉图的爱情观让人不可思议。而有一位美国学者却对今人所理解的这种柏拉图的爱情观，提出了新的见解。美国东西部社会学会主席、《美国家庭体制》一书的作者伊拉·瑞斯（Ira·reiss）经研究后认为，柏拉图推崇的精神恋爱，实际上指的是同性之间的一种爱，也就是“同性恋”。古希腊人认为，同性恋的过程更多地是灵交、神交，而非形交。而在女性很少受教育的古希腊社会，男人很难从女人中找到精神对手。这就是柏拉图偏重男性之间的爱情的原因。柏拉图坚信"真正"的爱情是一种持之以恒的情感，而惟有时间才是爱情的试金石，惟有超凡脱俗的爱，才能经得起时间的考验。
而美国的社会学者对“柏拉图式的爱情”是只有神交的“纯爱情”，还是虽有形交却偏重神交的高雅爱情，也众说纷纭。但有一点是可以肯定的，即柏拉图认为爱情能够让人得到升华。他说，对活得高尚的男人来说，指导他行为的不是血缘，不是荣誉，不是财富，而是爱情。世上再也没有一种情感像爱情那样深植人心。一个处在热恋中的人假如作出了不光彩的行为，被他的父亲、朋友或别的什么人看见，都不会像被自己的恋人看见那样，使他顿时苍白失色，失去一切的一切，无力面对自己爱的人和爱自己的人。
【柏拉图名言】
·在短暂的生命里寻找永恒
·爱是美好带来的欢欣，智慧创造的奇观，神仙赋予的惊奇。缺乏爱的人渴望得到它，拥有爱的人万般珍惜它。
· 爱情，只有情，可以使人敢于为所爱的人献出生命；这一点，不但男人能做到，而且女人也能做到。
· 尊重人不应该胜过尊重真理。
· 时间带走一切，长年累月会把你的名字、外貌、性格、命运都改变。
· 拖延时间是压制恼怒的最好方式。
· 初期教育应是一种娱乐，这样才更容易发现一个人天生的爱好。
· 人心可分为二，一部较善，一部较恶。善多而能制止恶，斯即足以云自主，而为所誉美；设受不良之教育，或经恶人之熏染，致恶这一部较大，而善这一部日益侵削，斯为己之奴隶，而众皆唾弃其人矣。
· 良好的开端，等于成功的一半。
· 最有美德的人，是那些有美德而不从外表表现出来，仍然感到满足的人。
· 好人之所以好是因为他是有智慧的，坏人之所以坏是因为人是愚蠢的。
· 一切背离了公正的知识都应叫做狡诈，而不应称为智慧。
· 不知道自己的无知，乃是双倍的无知。
· 没有什么比健康更快乐的了，虽然他们在生病之前并不曾觉得那是最大的快乐。
· 我们应该尽量使孩子们开始听到的一些故事必定是有道德影响的最好的一课。
· 法律是一切人类智慧聪明的结晶，包括一切社会思想和道德。
· 只有死者能看到战争的结束。
l 每天告诉自己一次：“我真的很不错”。
l 生气是拿别人做的错事来惩罚自己。
l 每个在恋爱中的人都是诗人。
l 无论你从什么时候开始，重要的是开始后就不要停止；无论你从什么时候结束，重要的是结束后就不要悔恨。
l 只要有信心，人永远不会挫败。
【柏拉图主义】
柏拉图主义（Platonism）是数学历史上影响最大的数学哲学观点，它起源于古希腊的柏拉图，此后在西方数学界一直有着或明或暗的柏拉图主义观念，19世纪，它在数学界几乎占了统治地。20世纪初，数学基础三大学派的争议刚趋平息，柏拉图主义观点又成为讨论的热点之一。
柏拉图主义的基本观点：数学的对象就是数、量、函数等数学概念，而数学概念作为抽象一般或“共相”是客观存在着的。柏拉图认为它们存在于一个特殊的理念世界里，后世的柏拉图主义者并不接受“理念论”，但也认为数学概念是一种特殊的独立于现实世界之外的客观存在，它们是不依赖于时间、空间和人的思维的永恒的存在。数学家得到新的概念不是创造，而是对这种客观存在的描述；数学新成果不是发明，而是发现。与之相应的，柏拉图主义认为数学理论的真理性就是客观的由那种独立于现实世界之外的存在决定的，而这种真理性是要靠“心智”经验来理解，靠某种“数学直觉”来认识的，人们只有通过直觉才能达到独立于现实世界之外的“数学世界”。
由于认为数学概念是一种真实的存在，所以现代柏拉图主义也被称为“实在主义”。柏拉图主义在西方近现代数学界有相当大的影响，一些数学巨匠如G．康托尔、罗素、哥德尔、布尔巴基学派基本上都持这种观点。一般认为，所以如此不是偶然的，这是数学反映客观世界，数学具有客观真理性这一素朴信念在哲学上的反映。而正因为如此，柏拉图主义对数学的历史发展就具有一定的积极作用：它促使数学家们在自己的研究中采取客观的科学的立场，而且，当某些高度抽象的数学理论因找不到现实原型而为人们所怀疑时，它也有可能给人们以一定的信念。尽管这种信念是盲目的，从而就有可能导致错误。
柏拉图主义的错误是显然的：把反映形式当作了认识对象；把抽象当作具体的客观存在；认为一种思维形式本身是客观的当然具有客观的真理性。离开人的实践来考察真理性必将导致谬误。柏拉图主义在哲学上是一种客观唯心主义。”
宣称信仰柏拉图主义并非意味着接受柏拉图的所有见解，而往往只是对如下特定思想的认同，即理念形式是存在的、永恒的，并比世界中的现象更实在、更完美，甚至是唯一真正实在和完美的实体。这个体系还包括认为理念形式只能由灵魂所认识等。
对柏拉图主义的辩护有：语言对象的抽象描述的一般性和其所描述对象的特殊性的对比；数学对象的抽象和毫无疑问的精确性等。
柏拉图主义中的理念形式在不同的情形下往往具有不同的意义。如：一类事物的名称；数学对象；自然定律等。
它以理念论为中心，包括宇宙论方面的宇宙生成说，认识论方面的回忆说，伦理观与社会政治观方面的四主德与理想国的学说，美学方面的“摹本”说，探求理念体系的概念辩证法以及教育学说等。是欧洲哲学史上第一个庞大的客观唯心主义体系，对后世西方哲学的影响极大。
【经济学图表：柏拉图】
柏拉图是为寻找影响产品质量的主要问题，用从高到低的顺序排列成矩形，表示各原因出现频率高低的一种图表。
柏拉图是美国品管大师朱兰博士运用意大利经济学家柏拉图（Pareto）的统计图加以延伸所创造出来的，柏拉图又称排列图。
【柏拉图式爱情】
柏拉图式爱情，以西方哲学家柏拉图命名的一种异性间的精神恋爱，追求心灵沟通，排斥肉欲。最早由Marsilio Ficino于15世纪提出，作为苏格拉底式爱情的同义词，用来指代苏格拉底和他学生之间的爱慕关系。
柏拉图认为：当心灵摒绝肉体而向往着真理的时候，这时的思想才是最好的。而当灵魂被肉体的罪恶所感染时，人们追求真理的愿望就不会得到满足。当人类没有对肉欲的强烈需求时，心境是平和的，肉欲是人性中兽性的表现，是每个生物体的本性，人之所以是所谓的高等动物，是因为人的本性中，人性强于兽性，精神交流是美好的、是道德的．
柏拉图式的爱情有以下的意义:
1. 理想式的爱情观 (比喻极为浪漫或根本无法实现的爱情观)
2. 纯精神的而非肉体的爱情
3. 男女平等的爱情观
4. 在这世上有, 且仅有一个人, 对你而言, 她(他)是完美的, 而且仅对你而言是完美的。也就是说, 任何一个人, 都有其完美的对象, 而且只有一个。
第一个意义最常被使用, 但其实是一个误解。不过既然大家都这样用, 也就算是另一个意义了。这误解来自于柏拉图的一个有名的著作"理想国"。该书探讨如何建构一个理想的国度, 因其或许过于理想化而难以实现, 故有人以此来诠释何谓柏拉图式的爱情。
第二个意义也经常被使用, 但基本上也是误解。这误解来自柏拉图的形上学, 他认为思想的东西才是真实的而我们看见的所谓的”真实世界”的东西反而不是真实的。
第三和第四个意义才真的是柏拉图的爱情观或两性观
柏拉图认为人们生前和死后都在最真实的观念世界, 在那里, 每个人都是男女合体的完整的人, 到了这世界我们都分裂为二。所以人们总觉得若有所失, 企图找回自己的"另一半"(这个词也来自柏拉图的理论)。柏拉图也用此解释为什么人们会有“恋情”。
在他的理论中, 没有那一半是比较重要的, 所以, 男女是平等的。而且, 在观念世界的你的原本的另一半就是你最完美的对象。他/她 就在世界的某个角落, 也正在寻找着你。
个人影响
柏拉图在西方的地位.柏拉图与他的学生亚里士多德比起来，在西方得到更多的尊重和注意。因为他的作品是西方文化的奠基文献。在西方哲学的各个学派中，很难找到没有吸收过他的著作的学派。在后世哲学家和基督教神学中，柏拉图的思想保持着巨大的辐射力。有的哲学史家认为，直到近代，西方哲学才逐渐摆脱了柏拉图思想的控制。
公元12世纪以前，亚里士多德的学说一直被教廷排斥，甚至欧洲已经不再流传亚里士多德的著作。当时，柏拉图的学说占统治地位，因为圣奥古斯丁借用和改造了柏拉图的思想，以服务神学教义。直到13世纪，托马斯・阿奎那利用亚里士多德的学说解释宗教教义，建立了烦琐和庞大的经院哲学。亚里士多德才重新被重视。
他对西方哲学的启蒙作用被普遍认可，也因为他卓越的人格而备受尊重。
因此，他被称为是西方哲学的奠基人！
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."