弗雷格的“思想”概念与柏拉图主义问题

Frege's Concept of “Thought” and the Platonistic Problem

由于承认像思想与数这样的抽象实体存在,弗雷格通常被认为是一个柏拉图主义者,因而面临柏拉图主义者通常面对的由贝纳塞夫提出的认识论问题,即在何种意义上我们可以认识这样的抽象实体。通过设置唯我论游戏,考察弗雷格的概念文字系统以及逻辑主义计划是否能够通过唯我论游戏的测试,可以证明弗雷格不会面临针对思想这个概念的柏拉图主义问题。通过分析卡罗尔问题,可说明弗雷格为何把思想理解为抽象实体,从而揭示思想这个概念的潜藏内涵。

Frege is usually regarded as a Platonist, for he recognizes the existence of abstract objects such as thoughts and numbers. He then faces the epistemological problem raised by Benacerraf: in what sense can we know about such objects? By devising the game of solipsism, and by considering whether Frege's Begriffsschrift and his logicistic project pass the test against that game, I argue in this paper that his notion of thought will not be confronted with the platonistic problem. Through examining the problem raised by Carroll, I explain why Frege understands thoughts as abstract entities, and uncovers the hidden motivation behind the notion of thought.