邏輯例外論及其困境

邏輯例外論的主要觀點是：邏輯是其他各門科學（包括自然科學、社會科學和人文科學）的例外，因為邏輯命題對於這個世界無所說，因其所含邏輯常項的意義而為真或為假；邏輯真理是分析的、必然的和先驗的，因而是不可修正的；邏輯規律對於如何正確思維具有規範性。邏輯例外論的代表性人物有Gottfried W. Leibniz、David Hume、Immanuel Kant、Gottlob Frege、Ludwig Wittgenstein 和Alfred J. Ayer等人。邏輯例外論已經遇到至少四個難題：如何證成邏輯規律？如何說明相互競爭的邏輯並從中選擇？如何說明邏輯規律的普遍可應用性？如何說明邏輯對於正確思維的規範性？全文的結論是：邏輯例外論像一種遁詞，建立在許多未加仔細辨證和批判性審查的預設之上，有很多難以克服的理論困難。

關鍵字

邏輯例外論；邏輯真理；分析性；必然性；先驗性；規範性

並列摘要

The main viewpoints of logical exceptionalism are that logic is exceptional with respect to all other sciences, including natural science, social science and humanities, because logical propositions say nothing about the world, and are true or false based on the meanings of logical constants; that logical truth is analytical, necessary and a prior, so it is not revisable; and that logical laws are normative for how to think correctly. The representative figures of logical exceptionalism are Leibniz, Hume, Kant, Frege, Wittgenstein and Ayer. Logical exceptionalism has encountered at least four problems: how to justify logical laws? How to explain the appearance of deviant and competitive logics and choose from them? How to explain the universal applicability of logic laws? How to explain the normativity of logical laws for correct thinking? The conclusion of this paper is that logical exceptionalism is like sort of evasion, based on many presuppositions without serious clarification and critical examination, and has many insurmountable theoretical difficulties.