雙棲性質的可能性及其對共相-殊相區分的影響

Abstract

本論文研究大衛．路易士（David Lewis）稱之為「雙棲性質」的一種特殊性質。雙棲性質具有可多重例現性以及可完全複製性的雙重特性，羅德里格斯．佩雷拉（Rodriguez-Pereyra）曾經論證過，由於承認這種性質可以解決過往理論所遇到的困難，我們應當認真看待建基於雙棲性質的理論。然而，承認這種性質的可能性亦會引發一系列值得探討的問題：它們應當歸屬於什麼範疇？是共性、殊性，亦或兩者皆非？除此之外，承認雙棲性質的可能性將會如何影響共相－殊相的區分原則？而建基於雙棲性質的個物理論又是否站得住腳？ 在這篇論文中我將指出，雙棲性質應當被看作自成一類的性質，與我所謂的「強共性」與「強殊性」皆屬不同範疇。為了達到這個結論，我們需要一個更加精緻的性質概念分類方式作為討論基準。而只要我們承認這個更加精緻的性質概念分類方式，一個新的共相－殊相的區分原則也就可以從中導出。我將論證，比起傳統的區分原則，例如「可多重例現性原則」以及「不可區辨性原則」，這個新的區分原則具有更多的理論優勢。需要注意的是，接受這個新的共相－殊相的區分原則，也意味著放棄共相－殊相區分之相互排除以及共同窮盡的特性。 在探討完關於性質本身特性的議題後，我轉而探討如何利用雙棲性質建構一個合理的個物理論。首先，作為可化約性理論，雙棲性質的叢束論除了如同羅德里格斯．佩雷拉所指出的那樣，可以用來回應「布拉克世界」（又稱為「雙球宇宙」）的挑戰外，我認為它也可以用來回應我所謂的「霍桑世界」的挑戰。因此它不僅優於共性叢束論，也優於殊性叢束論。而在不可化約性理論的方面，我也將提出我所認為建基於雙棲性質之上最有力的一種個物理論。

This essay examines a special sort of properties—what David Lewis once called “amphibians”—that are repeatable yet duplicable at the same time. As Rodriguez-Pereyra has plausibly argued, such a sort of property should be seen as a serious contender since postulating them can solve various difficulties facing traditional views. However, accepting the possibility of amphibians also raises several interesting questions: How should we categorize such properties? Should they be regarded as a sort of universals, tropes, or neither? How will the possibility of amphibians affect our view on a plausible principle of the universal-particular distinction? What will an appropriate theory of material objects look like under the Amphibianist ontology? In this essay, I will survey these issues in turn. As it turns out, we have reasons to regard amphibians as being a sui generis sort of properties distinct from what I call “strong universals” and “strong tropes.” To help ground this conclusion, a more fine-grained classification of different conceptions of properties is proposed. And once we adopt this classification, a new way of making the universal-particular distinction distinct from traditional views, such as the Repeatability Approach and the Indiscernibility Approach, can be directly derived from it. This new way of making the distinction, I will argue, is a more defensible one than its traditional rivals. An important result of accepting this approach, though, is that we should abandon the alleged mutually exclusive and jointly exhaustive nature that is often associated with the universal-particular distinction. After settling the issues concerning properties themselves, I turn to one of their most important applications: to build a theory of material objects. In this part of the essay, I first examine the reductionist amphibians bundle theory and argue that besides that it can account for the possibility of the Black World in an interesting new way, as pointed out by Rodriguez-Pereyra, and is thus preferable to the universals bundle theory, the theory can also account for what I call a “Hawthorne World” and is thus in one aspect superior to tropes bundle theory. I will also work out the preliminaries of what I believe to be the best version of the non-reductionist theory of material objects constructed out of amphibians. This latter view also claims to be more plausible than its traditional rivals in various aspects. The moral of all of these, I believe, is that an Amphibianist ontology is a more serious contender than one might have originally thought.