柏拉圖《泰鄂提得斯》201c以下對於「知識」的討論，被視為是「知識三條件」說法的古代來源，而這篇對話錄最後也反駁了知識三條件說。本文首先將返回文本，釐清柏拉圖這裡反駁三條件說的論證是什麼、討論中的「三條件」又是什麼？在做出上述的釐清之後，文中將進一步探討：如果對話錄最後反駁了三條件對知識的定義，柏拉圖是否以任何方式界定知識？實際上對話錄最後是在找不到任何對知識的定義下告終。但文中仍將試圖從和柏拉圖其他對於知識的論點相一致的方式，對此提出解釋，並以此作為了解柏拉圖「知識」概念的重要途徑。
Gettier objects the definition of knowledge as justified true belief, and mentions Plato's Theaetetus 201 as an ancient source of such definition. In fact, Plato objects some such definition in the dialogue, too. This paper will firstly explore Plato's arguments against such definition. It will secondly explore the definition discussed in the dialogue. This will show that Plato argues in quite a different way from modern epistemological discussions. The further question is what Platonic knowledge actually is. Since the dialogue ends without any firm conclusion, scholars have difficulties to define Platonic knowledge. However, this is consistent with Plato's other views on knowledge. If the dialogue provides any definition, it may merely persuade us with some belief, but not make us know. The aporetic ending of Theaetetus is an important key. Plato must show the way to search knowledge without offering a persuasive answer. From such a view, the way in which Plato searches the definition of knowledge is more significant rather than a definition of Platonic knowledge.
