「無」的形上學初探

 

 一、難以捉摸的虛無

當我們問「什麼是無？」時，我們已經墮入迷思的陷阱。所謂「無」，如果是「什麼」，便已經不是「無」了。這種困難並非單純語言上的遊戲，而是思維無法逃脫的邏輯糾結。舉例而言，當我們說「沒有獨角獸」，我們似乎在談論獨角獸這個東西，儘管它並不存在。這種語言現象揭示出：我們在否定某物的存在時，卻又不得不把它作為思考的對象。巴門尼德（Parmenides）早在古希臘就已經嚴正指出：一旦我們試圖合乎邏輯地談論「不存在」或「無」，就已違反了語言與思維本身的根本條件。對巴門尼德而言，「無」既無法被思考，亦無法被陳述，因為「說」本身就預設了「有」某物可說。
 

然而，「無」的問題並不因此結束。人類思想不斷回到這個根本的疑問：「為何有萬物，而不是什麼都沒有？」這個問題看似簡單，實則蘊藏著極深的哲學問題。因為「萬物之總和」若需一個外部的解釋，便要求我們跳出「萬物之總和」之外來尋找理由，但那是自相矛盾的。「無」的哲學問題考驗著我們的語言和理性的極限。  

 

二、物理學與「無」：現代科學的新詮釋

進入現代，隨著物理學的發展，「無」的問題被帶入了大眾討論的領域。特別是在量子宇宙論與真空理論中，「無」似乎不再只是哲學家的抽象難題，而成為可被討論、甚至可被檢驗的對象。科學界流行著一種說法：「宇宙可以從『無』中產生」。這樣的說法激發了許多想像與討論，但若我們細究科學家所指的「無」，會發現這個「無」其實遠非真正的「絕對虛無」。

在量子理論裡，所謂的「真空」並非一無所有，而是充滿了量子場和基礎結構。即使在所謂「什麼都沒有」的狀態下，仍存在著物理規則與各種潛在的可能性。這樣的「無」其實是一種「有」，並非徹底的空白。現代物理學雖然能夠推進我們對「無」的理解，但它所能處理的，始終是某種「有」的極限狀態，而非哲學上「一無所有」的「無」。

因此，雖然這些理論在科學上極具啟發性，但它們並未終結那個最根本的形上學問題：「為何會有任何東西？」這是因為科學的「無」仍然預設了一個可以發生變化的框架，而絕對的「無」則不容許任何性質、規則或過程的存在。
 

三、尋找「無」的困難：是錯誤的問題還是根本的限制？

當我們試圖尋找「無」，結果總是發現某種東西：一個背景、一種潛在的可能性。這種現象令人疑惑：究竟是「無」本身不可能存在？還是我們問錯了問題？這種困難並不僅僅是語言的限制。

回顧中國哲學，尤其是老子的思想，「無」從來不只是空洞的否定。對老子而言，「無」乃是萬有之本，是一切存在的深層基礎。「天下萬物生於有，有生於無。」在《道德經》中，老子反覆強調「無」的重要性：「道可道，非常道；名可名，非常名。無名天地之始；有名萬物之母。」這裡的「無」不是「甚麼都沒有」，而是指向一個無法被明確界定、無法被言說的根源性狀態。

老子用簡單而深刻的比喻闡明「無」的作用：「三十輻，共一轂，當其無，有車之用。埏埴以為器，當其無，有器之用。鑿戶牖以為室，當其無，有室之用。故有之以為利，無之以為用。」這些例子說明，正是因為中心的虛空，車輪才能運轉；正是因為器皿的空洞，才能盛載萬物；正是因為屋內的空間，人們才得以居住。世界的本質，並非只是「有」，而是「有」與「無」的通透與互補。 

因此，「無」不是一個可以被尋見的「東西」，而是一種透視世界的方式。若我們一味追問「無」作為某種存在，便落入了語言與思維的誤區。真正的「無」，或許不在於被發現，而在於被體會和參悟。
 

四、「無」作為方法與視野

哲學史上還有另一種對「無」的理解。卡普蘭（Kaplan）曾說：「只有透過無，才能看見世界，而不是看著無本身。」這句話意味著，「無」並非我們可以凝視的對象，而是我們觀看世界時所依賴的透鏡。中道思想也強調對「否定」、「空缺」與「虛無」的細膩關注：不是把「無」當作某個對象追逐，而是將其作為分析、理解與反思的技術。

這種方法要求我們在肯定與否定之間保持自我約束：只主張那些能被理性辯護的必然性。這樣的哲學態度，不僅能避免無謂的形上學幻想，也能提醒我們：「無」本身不是一個內容豐富的對象，而是理智與語言的極限。

在這個看法中，「無」之所以難以把握，正因為它不是眾多事物中的一個。它是一種「視界」，是一種「技術」。我們越能謹慎地運用「無」，它便越能照亮我們所擁有的——不是通過增加內容，而是通過顯現結構、澄清界限，是一種「負面啟示」。

 
五、「無」的極限與啟示：哲學的自我檢驗

「無」這個問題成為哲學的一面鏡子，檢驗著我們如何思考以及理解世界。當我們面對「無」的時候，實際上是在試探語言、邏輯與知識的邊界。「無」的概念提醒我們：不是所有疑問都能在現有的語言與理論框架中獲得解釋。我們需要另一種新的看法。
 

有些哲學家認為，「無」不過是一個語言的幻影，一種思維的誤區；另一些則主張，「無」作為極限概念，能讓我們反思世界的整體結構。無論採取何種立場，「無」的問題都拓展了我們的思考範圍，讓我們認識到自身的侷限與可能。正如老子所說，「有之以為利，無之以為用」——「無」不僅是一個問題，更是一種理解世界的方法。

藏天下於天下

鯤鵬之化

2022年DSE中文閱讀卷中，文言文引用了莊子《大宗師》中「藏天下於天下」之一段，被譽為「史上最難的DSE文言文」。引文如下：

死生，命也，其有夜旦之常，天也。人之有所不得與，皆物之情也。…

泉涸，魚相與處於陸，相呴以溼，相濡以沫，不如相忘於江湖。與其譽堯而非桀，不如兩忘而化其道。

夫大塊載我以形，勞我以生，佚我以老，息我以死。故善吾生者，乃所以善吾死也。

夫藏舟於壑，藏山於澤，謂之固矣。然而夜半有力者負之而走，昧者不知也。藏小大有宜*，猶有所遯。若夫藏天下於天下，而不得所遯，是恆物之大情也。

*：這裡不用考試局的「藏小於大有宜」，而用原文「藏小大有宜」。

本文旨在詮釋「藏天下於天下」的哲學涵義。試譯為白話後，我會根據我對莊子思想之理解道出「藏天下於天下」的兩層意義：(1) 無所謂「失去」，(2) 萬物為一，兩忘而化其道。由於我認為「泉涸」至「與其譽堯而非桀」一段和「藏天下於天下」沒有直接關聯，本文不會對這段詳解。

 

1. 引文試譯

生死乃必然，它們像日夜交替般平常。人總有不如意，這是事物之實情。…

湖乾了，魚困在地上。牠們與其互相吐水維持生命，不如在江湖中忘記水的存在。與其讚譽堯而咒罵桀，不如忘了兩者而融入「道」之中。

大地賦予我形體，以生命使我勞動，以年老使我安佚，以死亡使我休息。所以安於生命的人，也安於死亡。

把船藏於山中，再把山藏於湖澤之中，可謂非常穩固了。但晚上如有力士把它背走，愚蠢的人不會知道。把小物藏於大容器內是合宜的，但也有失去的可能。若果把天下藏於天下，就不會失去了，這是永恒的萬物之實情。

 

2. 「藏天下於天下」的第一層意義：無所謂「失去」

上面講到「把天下藏於天下，就不會失去」，為甚麼？我們通常把東西藏在容器內，將其遮蔽起來，以防被人取走。但是如何「藏天下」呢？「天下」包括一切，沒有更大的容器可以藏起天下；但反過來，也因無人能藏起天下，不會有人能把天下取走。

然而，「藏天下」有何意思？我們如想擁有一個東西，就會藏起它。但莊子告訴我們，無論藏得多好，也有可能失去；事實上隨時間流逝，一切必將失去*。史上擁有最多的君王，死了也會失去一切；再偉大的帝國也會消亡。所以，如果我們不想失去，只要擁有天下就行了！而「藏天下」也只有「於天下」了。

*: 一說《大宗師》的「有力者」是指時間

然而，不擁有人和物，只「擁有天下」，這和沒有擁有又有何分別？這樣的「擁有」有誰稀罕？這可在莊子的其他著作中找到答案，《齊物論》如此說道 ：

非彼無我，非我無所取。是亦近矣，而不知其所為使。

如果沒有「非我」的觀念，就沒有「我」的觀念了。所以說「我擁有X」，就是把我和X區分開來。但「我」和「非我」也有相似之處（如二者都由物質構成），為何要如此區分？莊子認為，一切區分都是始於世俗的言語、知識和由此而來的既有觀念，這些區分都是任意和虛妄的。

如果沒有「我」和「非我」，也就沒有「擁有」，天下只是天下，是渾而為一的；沒有「擁有」，也就無所謂「失去」。「藏天下於天下」的道理，不是教人如何不會失去，而是使「失去」變成沒有意義。

 

3. 莊子的「道」和「化」

要明白莊子「萬物為一」和「兩忘而化其道」的意思，必須先了解莊子的「道」和「化」。

3.1 道

莊子在《大宗師》寫道：

夫道，有情有信，無為無形；可傳而不可受，可得而不可見；自本自根，未有天地，自古以固存；神鬼神帝，生天生地；在太極之先而不為高，在六極之下而不為深；先天地生而不為久，長於上古而不為老。

道是無形的，自有永有，存在於世上任何一個地方和事物之中。（《知北遊》說道在「屎溺」）「道」是一種幾近自然規律的，形而上的存在，它主宰萬物之流變，其本身卻沒有意志和好惡。萬物跟隨道的流變，就是所謂「化」。

 

3.2 化

《至樂》中說到莊子的妻子之死：

莊子妻死，惠子弔之，莊子則方箕踞鼓盆而歌。惠子曰：「與人居長子，老身死，不哭亦足矣，又鼓盆而歌，不亦甚乎！」

莊子曰：「不然。是其始死也，我獨何能無概然！察其始而本無生，非徒無生也，而本無形，非徒無形也，而本無氣。雜乎芒芴之間＃，變而有氣，氣變而有形，形變而有生，今又變而之死，是相與為春秋冬夏四時行也。人且偃然寢於巨室，而我噭噭然隨而哭之，自以為不通乎命，故止也。」

＃：有和無之間

人誕生之前，本來是沒有形體和生命的物質。全因為道之所行，人才由「氣」聚成形體和有生命；而也因為道之所行，人才會死亡和腐化，歸於天地，這就像四時變化一樣，周而復始。人和天地一樣，都只是在順乎道的規律下變化。莊子又說：

道無終始，物有死生，不恃其成；一虛一滿，不位乎其形。年不可舉，時不可止；消息盈虛，終則有始。是所以語大義之方，論萬物之理也。物之生也若驟若馳，無動而不變，無時而不移。何為乎？何不為乎？夫固將自化。

《秋水》

道是永恒的存在，無始無終，沒有任何東西能阻止。萬物卻有生死、盈虛和始終，它們無一時固定，它們自己不斷都在隨時間變化。

 

4. 「藏天下於天下」的第二層意義：萬物為一，兩忘而化其道

4.1 萬物為一

上面提到《齊物論》中莊子破除「我」和「非我」之分別。在同一章他也借公孫龍「指非指」和「白馬非馬」的詭辯說明他自己的道理：

以指喻指之非指，不若以非指喻指之非指也；以馬喻馬之非馬，不若以非馬喻馬之非馬也。天地，一指也；萬物，一馬也。

《齊物論》

《德充符》又道：

自其異者視之，肝膽楚越也；自其同者視之，萬物皆一也。

「（手）指」與「非指」之分，「馬」與「非馬」之分，是言語和知識帶給我們的概念，是虛妄的，所以必然是充滿邏輯上的缺陷。萬物皆有相同、相異之處，這些異同不構成分辨他們之理據；「指」和「馬」本和世上其他東西都相似，一切皆可渾為一體。

這也適用於「我」和天地之關係：

天地與我並生，而萬物與我為一。《齊物論》

不是「我」是天地之一部份，而是萬物本身就是一個不可分割的整體，而「我」只是後來由言語和知識所建立的概念。

 

4.2 兩忘而化其道

如果萬物為一，那麼，「藏天下於天下」是怎樣的一個人生境界？

上面我們看到，莊子於妻死時「噭噭然隨而哭之，自以為不通乎命，故止也。」（《至樂》）莊子因妻死而傷心，但反省自己的哀傷是因為不了解「人必順應萬物流變而有生死」之道理，因此停止了哭泣。

莊子盆鼓而歌，不是因為快樂，而是展現了一種通達超脫之情懷。人與萬物同為一體，所謂「生死」只是天地循「道之所行」之自然而然的變化。而認為有「得失」，則是因為由知識和經驗產生之偏執，進而產生的錯覺。《至樂》另一段又說：

滑介叔曰：「亡。予何惡？生者，假借也；假之而生生者，塵垢也。死生為晝夜。且吾與子觀化而化及我，我又何惡焉？」

生命不過是物質湊合而暫時「假借」而來，生死如晝夜更替般平常。如果明白這道理的話，又怎會厭惡天地給我們的身體和事物呢？所以安於生命的人，也必安於死亡。

莊子利用「藏天下於天下」的道理，道出世上本無所謂得失，而這進一步是因為「萬物為一」，而有此覺悟者，可擺脫世俗灌輸給我們的種種偏執，不稀罕「擁有」，從由「得失」而來的恐懼中解放出來，樂於融入「道」的大同之中。這種心靈上的轉化，是順應自然，效法道的變化。

 

5. 結語

莊子善於用表面荒誕的故事和道理，讓人突破常識中理所當然的觀念，此中包括「我」、「非我」和「得失」。「藏天下於天下」表面非常荒謬，然而細思之下，人知道任何東西終歸都會失去，只有「天下」才不可能丟失。這知識看來十分無用，但若人了解「我」、「非我」和天下是一體的話，就會知道無所謂「失去」。人可從對「得失」的恐懼中被釋放出來。我們進而可以物我兩忘，從精神層面上自我轉化，融入「道」的運行之中。

 

非物質的靈魂存在嗎?

 「靈魂」是人類其中一個最久遠的概念。

它似乎解釋了許多東西：人的同一性(personal identity)，以及智慧和意識之來源。

而物質如何產生意識，更是迄今科學未能解決，連頭緒也沒有的難題。

然而，儘管幾百年來的努力，現代科學並沒有找到靈魂存在的確鑿證據。

如果說靈魂是「超自然」的，是否就解決了這問題？

以下是我在讀哲學碩士「科學與理性思考」課程時，期末論文的一部份的答案。

 

 

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Question:

3. What are the major arguments for and against mind-body dualism? What impacts does the development of neuroscience have on the traditional view of mind? Do you think that it is reasonable to believe in the existence of an immaterial soul? Why or why not?

 

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Q3:   (Immaterial soul and mind) 

In this essay, I will focus on the discussion of interactionist substance dualism, which posits the existence of a physical world and immaterial soul (“soul” hereafter), and the two can interact. It is because (1) this form of mind-body dualism is the most popular, and (2) other forms of dualism (e. g. property dualism and epiphenomenalism) do not contradict with physicalism as much as the dualism I will write about.

Since most people believe in the existence of a physical world, I shall also use the arguments for and against the existence of soul, as those for and against dualism, respectively.

 

1.   Arguments for immaterial soul

 

       1.1   Mental-physical distinction

                  Philosopher Frank Jackson proposed a thought experiment: how “red” feels like is irreducible to knowledge about the physical world. [1] To many, the “soul hypothesis” has a crucial function to explain mental phenomena. Humans and some animals are very different from other entities: we have the abilities to perceive, remember, be self-conscious, think and have intention.

                 Plants and dead matters do not seem to share those. They are governed only by the blind physical laws of the universe which we can study openly. On the contrary, it seems that we each have the “privileged access” of our own mental content.

                 There seems to have an insurmountable gap between the mental and the physical, therefore it seems reasonable to theorize something other than the physical entities, which we call the “soul”, which is the bearer of the mental qualities.

 

 

       1.2   Personal Identity

                  There are also philosophical problems of what a person is, and how we can recognize if two persons are the same (e. g. a boy and an old man, at different times). Many theories are proposed, e. g. the body and psychological continuity criteria; but they are all unsatisfactory. Some suggested to give up the idea of person altogether. [2][3]

                 But the idea of personal identity is so natural and important to us: personal relationships, responsibility and ownership all depend on it. This problem has motivated some of us to believe in the existence of soul. Because a soul is immaterial, it cannot be divided; if every soul is unique and permanent, then we can distinguish two persons by their souls.

 

 

2.   Arguments against immaterial soul

 

       2.1   Problems of Interaction

                  The soul hypothesis has caused many conceptual problems. Soul is non-physical and thus very different from physical objects. If so, how can souls cause the changes in the physical human body? On the other hand, how do the stimuli caused by the external world on the physical body can possibly affect and be perceived by the immaterial soul?

                  Some people claim that they have seen ghost figures, or say that ghosts can scare or harm people. However, if these “ghosts” are non-physical souls, then how can they be seen? Being immaterial, they cannot interact with light to see people either. Philosopher Daniel Dennett said the idea of ghost is self-contradictory: sometimes they can pass through walls, but at other time they can move objects. [5]

 

 

       2.2   Incompatibility with science

 

                 The problem of interaction was just one of the many conflicts between the idea of soul and modern science.

                 Physics: In science, all events are physical, and any event is caused by a previous event in accordance to physical laws. Soul by definition is not physical, and therefore if it interacts with the physical world (e. g. a person raising her hand), there would be events not caused by other physical events. This violates the causal closure principle of physics.

 

                 Even if the soul can somehow cause physical events, there is still a scientific problem. Physicist Sean Carroll wrote that if there is any “spirit particles/ forces”, we would have already detected it. [6] If there is an event without a physical cause, it may also break the law of conservation of energy.

                 Neuroscience: Much has been known about how the brain works since the idea of soul. It is well-known that many physical alterations to brain can change the mental qualities we attribute to soul. These includes brain damage, tumor, psychiatric disorder, memory loss, electrical and magnetic stimulations, pharmacological and optogenetic manipulations, resulting in memory loss, change in perceptions, beliefs and personality. Neuroscientist David Eagleman described a patient with pedophilic tendency increases over stages of brain cancer. [7] Libet’s experiment and other similar experiments suggest that “our decisions” form in the brain before we “decide” them. [4]

                 If we can correlate all mental activities with regions of the brain, how can we still say that we must need a soul to account for the mental phenomena?

                 Since science has been so successful in explaining the natural world, it follows that if we have no strong reason to believe in soul, when science and the soul hypothesis are in conflict, we should abandon the latter.

 

 

3.   Possible responses

 

       3.1   Soul as an Explainer

 

                 In response to the problems of interaction, philosopher Richard Swinburne said our inability to understand how soul interacts with physical body does not mean they do not interact. [8] The mental-physical distinction is still very clear that we need soul to explain the mental phenomena as well as personal identity.

                 This line of thinking is analogous to the use of the idea of immaterial “vital force” to explain how dead matter can constitute living things. Nowadays, scientists generally agree that organisms emerge out of the complex arrangements of molecules and the chemical reactions among them. “Vital force” plays no part in this scheme, because it is not needed: we have known enough about organisms. Biologist Julian Huxley jokingly compared vital force to “locomotive force” which makes the vehicles move. [9] Similarly, the soul hypothesis may one day play no part in our explanation of mental phenomena.

                 Furthermore, the soul does not seem to explain personal identity satisfactorily. For if souls are immaterial, that they do not occupy spatial location, how can we distinguish one soul from another? There is also the problem of counting the number of souls: e. g. consider two persons, each with half of a brain; if the half-brains are put into the same body, is there one soul or two souls? [3] It seems that the concept of personal identity is one which is helpful to us in daily social situations instead of imaginary cases. It is erroneous to infer an immaterial entity from a confusing concept.

 

 

       3.2   Incompatibility with Science

                  Soul theorists, if not dismissing a large part of science, may respond to the disagreements between their hypothesis and science in the following ways.

                  First, altering brain structures and activities may seem to change the mental activities. However, we may compare the relationship between a brain and a soul, with that between a violin and its player. If the violin is broken, the bad play may not be due to the skill of the violinist; similarly, the alteration of the brain does not imply that of the soul. [10]

                  Second, some may distinguish mind from soul, with the mind being physical and responsible for the mental phenomena. Soul does not directly interferes with the physical world through the mind, thus is not in conflict with any physical laws or the results of neuroscience.

                  These auxiliary theories may indeed avoid the conflicts between science and the soul hypothesis, however with bad consequences. For they take away the explanatory power of the soul, which was once the main reason of the soul hypothesis. Soul has become something without any function or effect. If everything can be explained through the physical events, by Occam’s Razor we have no need of the presupposition of a soul.

 

In conclusion, because of the (1) incompatibility between the soul hypothesis and science, (2) problems of interaction between soul and physical objects, and (3) failure of the soul hypothesis in explaining personal identity, there is no rational reason to belief in immaterial soul and therefore mind-body dualism.

 

Reference:

  

[1]     Jackson, F. (1982). Epiphenomenal qualia. Philosophical Quarterly, 32(127), 127–136.

 

[2]     Parfit, D. (1971). Personal identity. The Philosophical Review, 80(1), 3-27.

 

[3]     Parfit, Derek. “Divided Minds and the Nature of Persons” in Edwards, Paul (Ed.). Immortality. Prometheus. 1997, pp. 308-315.

 

[4]     Libet, B., Gleason, C. A., Wright, E. W., & Pearl, D. K. (1993). Time of conscious intention to act in relation to onset of cerebral activity (readiness-potential). In Neurophysiology of Consciousness (pp. 249-268). Birkhäuser, Boston, MA.

 

[5]     Dennett, Daniel. Conciousness Explained. Back Bay Books. 1992.

 

[6]     Carroll, S. M. (2011, May 23). Physics and the Immortality of the Soul. Retrieved from https://blogs.scientificamerican.com/guest-blog/physics-and-the-immortality-of-the-soul/

 

[7]     Choi, C. (n.d.). Brain tumour causes uncontrollable paedophilia. Retrieved from https://www.newscientist.com/article/dn2943-brain-tumour-causes-uncontrollable-paedophilia/

 

[8]     Swinburne, Richard. The Evolution of the Soul. Oxford University Press. 1997.

 

[9]     Gillies, Mary Ann. (1996). Henri Bergson and British Modernism (revision of author’s PhD thesis), (pg. 31). McGill-Queen’s Press.

 

[10]   Calef, S. (n.d.). Dualism and Mind | Internet Encyclopedia of Philosophy. Retrieved from https://www.iep.utm.edu/dualism/