先驗邏輯與精神發展-陳那與康德批判知識論的研究

Abstract

佛家哲學與康德哲學不約而同地要求著我們一方面必須被限制在制約著一切可能現象的自然因果律當中，卻又同時要求著我們可以從這個制約當中追尋精神上的解脫。這個不相容卻又互為需要的一種特殊依存關係，在佛家，我們有「輪迴」與「涅槃」；在康德，我們有「自然」與「自由」。康德堅信先驗認識論是解釋這個關係的必要途徑，但是這個立場顯然難以輕易為後人所理解，以至於直到現在哲學家們仍然必須很努力來為康德辯護。另一方面，佛家哲學探討認識論是否構成恰當的手段來釋開這個關係，而不同的看法導致大乘佛教分裂為中觀學派與瑜伽行學派，而中觀學派又分裂為自續與應成兩派。\n\n在康德學與佛學傳統中對知識論的一般理解，因為傾向于將認知系統理解為本體地運作在時間當中，於是導致上述難題不易辨清。本文嘗試展示對知識論的本體價值預設是理解康德先驗觀念論的障礙，也造成知識論，特別是陳那所提出的反實在論知識論，在佛家解脫計劃中地位未定的原因。本文也嘗試透過解除對認知系統的本體論預設建立本文所謂的「批判知識論」，進而分別地在兩個傳統中為知識論的地位辯護。這包含著我們在自然因果關係之外，還需要一個另外的他種因果關係（自由的因果），不論就文獻來說，或者就哲學系統來說。自由因果只確立認知的因與一切可能認知之間的關係，而自然的因果只在認知的結果之中有效卻不可能對認知的因有效。雖然這兩種因果關係彼此獨立地作用，它們在所有可能認識的實現之中形成一個形式的統一。這兩種因果關係的正交，明確地將一個個人的自由狀態（反身地正在認知中）與被限制狀態（反身地被認知）區分開來； 更甚，其空內積，也就是這兩種因果關係對彼此的無效，造就了一切可能被實現的認識之中，「理想」與「現實」這兩個向量空間的可能性， 也因此拱起了一個單一的「經驗」世界。

In Buddhism and in Kant, there exists a common quest for an incompatible yet harmonious mutual dependence between the constraining of all possible phenomena within the bounds of natural causality and the spiritual liberation from such causal chains: saṃsāra vs. nirvāṇa in Buddhism and nature vs. freedom in Kant. Kant believes that transcendental epistemology is necessary to resolve\nsaid paradox, and this position has proven so incomprehensible for later thinkers that\nphilosophers nowadays still feel compelled to defend Kant. Meanwhile, in Buddhism,\ndebates continue to rage on whether epistemology constitutes a proper means to\nexplain the dependence, and such debates have resulted in the split of Mahāyāna Buddhism into Madhyamaka and Yogācāra, and subsequently Madhyamaka into Svātantrika and Prasaṅgika. \n\nThe mainstream understanding of the epistemology in the philosophical traditions of Kant and Buddhism is problematic because the cognitive system is understood to be operating ontologically in time. I shall attempt to demonstrate that the ontological assumption in the mainstream understanding is the root cause for both the difficulty in appreciating Kant`s transcendental idealism and the indeterminable position of epistemology in Buddhism, especially Dignāga`s anti-realistic epistemology. I will also defend epistemology by denying the ontological attribution to the epistemic system and by establishing what I term “critical epistemology.” This entails focusing on the need for an additional, distinct kind of causality (causality of freedom) on top of the natural causality in both traditions, be it textually or philosophically. The causality of freedom only necessitates the cause of cognition and its relation to all cognitions, whereas the causality of nature is only effective in the results of cognition but never on the cause of cognition. Although the two kinds of causality operate independently, they constitute a formal unity in the realization of every possible cognition. The orthogonality between the two kinds of causality sharply distinguishes the free (reflexively cognizing) status from the constrained (reflexively cognized) status of a person; furthermore, its empty inner product, i.e., the empty impact these two kinds of causality exert upon each other, makes sense of each vector subspace (dimension), namely ideality and reality, in all possible realized cognitions, thus culminating in a single world of “experience.”