利貝特腦神經科學實驗是否足以否定自由意志的存在？

Can Libet’s Neuroscientific Experiments Negate the Existence of Free Will？

張凱傑(Kai-Chieh Chang)

指導教授 ： 祖旭華

臺北醫學大學/人文暨社會科學院/醫學人文研究所/碩士(2013年)

https://doi.org/10.6831/TMU.2013.00020

摘要

本論文處理的核心問題是: Libet的腦神經科學實驗是否足以否定自由意志的存在? 我的答案是否定的。本論文將企圖證明這一點。我的論證策略如下: 第一章介紹Libet的腦神經科學實驗如何衝擊到自由意志的存在。在第二章中，我會詳細說明Libet的腦神經科學實驗的實驗設計與數據，以及Libet對於其實驗結果的詮釋。在第三章中，我會介紹Mele所提出的新詮釋及Mele對Libet詮釋的批判。在第四章中，我說明為何即便Mele所提出的新詮釋是正確的，Mele也未必能挽救自由意志的存在。在第五章中，我提出我個人對於Libet實驗的批判。這個批評分為三個部份：首先，Libet認為若要證明自由意志存在，必須要預設實體二元論成立，因為自由意志乃是一種非物質性的心理狀態。但我認為要證明自由意志的存在不需要預設實體二元論。第二，Libet將無意識的大腦活動，視為是決策者(decision-maker)，因此大腦對於行為會構成因果關係，但我將論證大腦活動對於行為的產生僅具有相關性(correlation)。最後，Libet將「否決權」視為自由意志的展現，將引發道德責任歸屬上的不對稱性。

本論文的結論是: Libet的腦神經科學實驗不足以否定自由意志的存在。

關鍵字

腦神經科學 ； Libet ； Mele ； 自由意志 ； 自由否決意志 ； 覺知的意志 ； 否決權

並列摘要

The core issue in this thesis is: Can Libet’s neuroscientific experiments negate the existence of free will？ My answer is that they cannot. This paper attempts to prove this viewpoint. My argumentative strategy is as follows. The first chapter describes how Libet's neuroscientific experiments challenged the existence of free will. In the second chapter, I explain in detail the experimental design and data in Libet's experiments as well as Libet’s interpretation of the results. In the third chapter, I introduce the new interpretation proposed by Mele and his criticism of Libet’s interpretations. In the fourth chapter, I explain why Mele may not be able to save the existence of free will, even when we concede, for the sake of the argument, that his interpretation is correct. In the fifth chapter, I propose my criticism of Libet’s experiments. My criticism is based on the following: first, Libet believed that to prove the existence of free will, we must presuppose the truth of dualism because free will is a non-material mental state. However, I propose that dualism is not necessarily required to prove the existence of free will. Second, Libet regarded the unconscious brain activity as decision-maker, and thus held that there is a causal relationship between brain and action. However, I argue that there is merely a correlation between brain activity and action. Finally, Libet considered the right of "veto" a manifestation of free will. I argue that this leads to an absurd asymmetry in the attribution of moral responsibility.

The thesis concludes that Libet’s neuroscietific experiments cannot negate the existence of free will.

並列關鍵字

neuroscience ； Libet ； Mele ； free will ； free won’t ； conscious will ； veto

參考文獻

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