The Dual Components of Perceptual Experience

在經驗中我們直接知覺到世界萬物，然而主流哲學進路中的「間接知覺理論」否定了這樣的常識論點，主張我們透過某些元目－外在對象所引發的感官性質－來觀看萬物。本文說明一特定之直接理論，最初由里德（Thomas Reid）與康德（Immanuel Kant）所創倡，近代則有賽勒斯（Wilfrid Sellars）與麥克道歐（John McDowell）以及其他學者相繼發展。根據此理論，知覺經驗涉及感覺與概念能力之相互作用，此進路因此可被歸類於二元論。一般反對知覺之二元論的理由有三：第一，若感覺僅僅因果地促成知覺，則經驗證成並無可依賴之基礎；第二，二元論似乎將知覺等同於判斷，然而「看見」和「相信」可以是相互獨立的狀態；第三，二元論主張語意指稱（信念意向性）優先於知覺指向（知覺意向性）。本文指出修正的賽勒斯式二元論能夠解決以上三點反對意見。首先，在此二元主義架構下，感覺並非因果造成知覺，反而是組構成知覺，如此一來，經驗證成並不受到威脅。其次，二元論事實上包含兩種「看見」的意涵，其中只有一種意涵會將知覺等同判斷。最後，二元論申明語意指稱和知覺指向是相互依存，因此排除兩者之間具有優先性關係。

關鍵字

知覺；經驗；二元論；意向性

並列摘要

In experience we perceive things in the world in an immediate manner. However, a dominant philosophical approach, the indirect theory of perception, denies this commonsense view and contends that we see things through something else-some sort of sensory qualities caused by physical objects. In this paper I present a direct theory originally advocated by Reid and Kant and developed in recent time by Sellars, McDowell, and others, according to which perceptual experience involves the interplay between sensory and conceptual capacities, and in light of this the approach merits the label dualism. There are three objections generally raised against dualism. First, if sensations merely cause perceptions, then empirical justification rests on dubious grounds. Second, dualism seems to identify perception with judgment; however, seeing and believing can be independent states. Third, dualism regards semantic reference (the intentionality of belief) as prior to perceptual directedness (the intentionality of perception). I argue that an enriched Sellarsian dualism can meet all three objections. First, I portray a dualist framework in which sensations not merely cause but constitute perceptions, and as a result empirical justification can be restored. Second, different senses of seeing are examined and in only one sense is perception identified with judgment. Third, dualism maintains that semantic reference and perceptual directedness are mutually dependent, and thus there is no priority relation between them.