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Contemporary philosophy
當代哲學
Pump-primer
“直覺泵”入門
Tools for pondering imponderables
用來思考難以解釋的事物的工具
Intuition Pumps and Other Tools for Thinking.By Daniel Dennett.
《思考的工具：直覺泵及其他》
“THINKING is hard,” concedes Daniel Dennett. “Thinking about some problems is so hard that it can make your head ache just thinking about thinking about them.” Mr Dennett should know. A professor of philosophy at Tufts University, he has spent half a century pondering some of the knottiest problems around: the nature of meaning, the substance of minds and whether free will is possible. His latest book, “Intuition Pumps and Other Tools for Thinking”, is a precis of those 50 years, distilled into 77 readable and mostly bite-sized chapters.
丹尼爾·丹尼特承認：“思考是困難的。思考某些問題之難，幾乎到了只要一想到要思考這些問題就會頭疼的地步。”對此，丹尼特深有體會。作為塔夫斯大學的一名哲學教授，在過去半個世紀里，他一直在試圖解開我們身邊那些最難以解決的問題：語言含義的本質，人類心靈是由什么組成的以及自由意志是否可能等。日前，他把自己50年來的思考濃縮為77篇既有可讀性又短小精悍的文章，匯集成冊后取名為《思考的工具：直覺泵及其他》
“Intuition pumps” are what Mr Dennett calls thought experiments that aim to get at the nub of concepts. He has devised plenty himself over the years, and shares some of them. But the aim of this book is not merely to show how the pumps work, but to deploy them to help readers think through some of the most profound conundrums.
“直覺泵”是丹尼特用來稱呼思想實驗的一個詞語。所謂思想實驗就是一種意在探究概念核心內容的實驗。在書中，他同讀者一起分享了這些年來為自己所設計的許多此類實驗。但是，他寫作本書的目的不僅僅是要展示“直覺泵”的工作流程，更重要的是通過使用“直覺泵”，幫助讀者去思考那些最深奧的難題。
As an example, take the human mind. The time-honoured idea that the mind is essentially a little man, or homunculus, who sits in the brain doing clever things soon becomes problematic: who does all the clever things in the little man's brain? But Mr Dennett offers a way out of this infinite regress. Instead of a little man, what if the brain was a hierarchical system?
下面，就讓我們以“人類的心靈”為例來介紹一下丹尼特的“直覺泵”理論。傳統的觀點認為，從本質上說，心靈是一個住在人類大腦里從事智力活動小人，或者侏儒。不過，在丹尼特看來這種觀點是站不住腳的：既然如此，那么，住在這個侏儒的大腦中，從事智力活動的人又是誰呢？對此，丹內特提供了一種走出此類無限回歸的方法。在他看來，如果大腦不是一個侏儒，而是一個分級系統，情況會如何呢？
This pump, which Mr Dennett calls a “cascade of homunculi”, was inspired by the field of artificial intelligence. An AI programmer begins by taking a problem a computer is meant to solve and breaking it down into smaller tasks, to be dealt with by particular subsystems. These, in turn, are composed of sub-subsystems, and so on. Crucially, at each level down in the cascade the virtual homunculi become a bit less clever, to a point where all it needs to do is, say, pick the larger of two numbers. Such homuncular functionalism replaces the infinite regress with a finite one that terminates at tasks so dull and simple that they can be done by machines.
丹內特把這種泵稱之為“級聯侏儒”，其靈感自于人工智能領域。在人工智能領域，當一名程序員接受了一項準備交給計算機去解決的任務時，他首先會把這項任務分解為一些更小的任務，然后再把這些更小的任務交給一些特定的子系統去解決，而這些子系統又是由更小的子子系統組成的，以此類推。這一過程的關鍵在于，在這個串聯在一起的每一個較低層次的子系統中，那個虛擬侏儒會漸漸地變得不再那么聰明，直至到達這樣一個點為止。在這個點上，需要那個侏儒來做的全部事情就是在兩個數字中選出較大的那一個。這樣，這種侏儒技能主義就用有限回歸代替了原來的無限回歸，而這種有限回歸能夠在任務變得非常單調又非常簡單以至于只需機器就可以完成的時候自動停止。
Of course the AI system is designed from the top down, by an intelligent designer, to perform a specific task. But there is no reason why something similar couldn't be built up from the bottom. Start with nerve cells. They are certainly not conscious, at least in any interesting sense, and so invulnerable to further regress. Yet like the mindless single-cell organisms from which they have evolved, each is able to secure the energy and raw materials it needs to survive in the competitive environment of the brain. The nerve cells that thrive do so because they “network more effectively, contribute to more influential trends at the [higher] levels where large-scale human purposes and urges are discernible”.
人工智能系統當然是由一位有智慧的設計師，為了完成某項特殊的任務，按照由上至下的原則設計出來的。既然如此，那么就沒有理由不能按照從下至上的原則建造一個同樣的系統。以神經細胞為例，這些細胞當然是沒有意識的，他們幾乎沒有任何有趣的感覺，它們非常脆弱，再也經不起進一步的回歸。然而，就像它們從中進化而來的、沒有思維能力的單細胞器官一樣，這些神經細胞中的每一個都具備獲取所需的能量和原料的能力，這種能力確保它們能在互相競爭的大腦環境中生存下去。那些茁壯成長的神經細胞之所以這樣做，是因為他們“串聯在一起時的工作效率更高，對[更高]層次那些更有影響力的趨勢做出了貢獻，而這些更高的層次可以辨識大量的人類意識。”
From this viewpoint, then, the human mind is not entirely unlike Deep Blue, the IBM computer that famously won a game of chess against Garry Kasparov, the world champion. The precise architecture of Mr Kasparov's brain certainly differs from Deep Blue's. But it is still “a massively parallel search engine that has built up, over time, an outstanding array of heuristic pruning techniques that keep it from wasting time on unlikely branches”.
由此來看，心靈并不是完全不同于“深藍”的東西。“深藍”是由IBM公司設計建造的一臺計算機，它因在一場比賽中戰勝了國際象棋世界冠軍加里·卡斯帕羅夫而名噪一時。卡斯帕羅夫大腦的精確架構肯定有別于“深藍”。不過，即便如此，“深藍”的大腦仍舊是“人類到目前為止按照啟發式剪枝技術陣列而建造的一臺能夠進行大規模并行運算的搜索引擎，啟發式剪枝技術陣列是一種先進的技術，它能夠讓搜索引擎不把時間浪費在不可能的選擇之上。“
Those who insist Deep Blue and Mr Kasparov's mind must surely be substantially different will balk at this. They may well be right. But the burden of proof, Mr Dennett argues, is on them, for they are in effect claiming that the human mind is made up of “wonder tissue” with miraculous, mind-moulding properties that are, even in principle, beyond the reach of science—an old-fashioned homunculus in all but name.
讀到此處，那些堅持“深藍”與卡斯帕羅夫的心靈一定是由不同物質構成的人定會咆哮不已。他們也許是對的。但是，丹內特指出，如果如此的話，那么證明這一理論的重擔就落在了這些人的身上。這是因為，他們的觀點實際上是在宣稱，人類心靈是由具有不可思議的、能夠影響心靈的性能的“非同一般的組織”所組成的。但是，從理論上來說，這些組織已經超出了科學的認知范疇—實際上，它們不過是一種已經過時的侏儒而已。
Mr Dennett's book is not a definitive solution to such mind-benders; it is philosophy in action. Like all good philosophy, it works by getting the reader to examine deeply held but unspoken beliefs about some of our most fundamental concerns, like personal autonomy. It is not an easy read: expect to pore over some passages more than once. But given the intellectual gratification Mr Dennett's clear, witty and mercifully jargon-free prose affords, that is a feature, not a bug.
丹內特的書并不是對此類讓頭腦發暈的問題的終極答案。相反，他的書是對此類問題的終極思考。這就如同那些有意義的終極思考一樣，該書通過讓讀者對那些深藏于我們內心卻又無法言說的信念進行檢討，從而達到自己的目的。這不是一本容易讀懂的書。因此，我們希望讀者在閱讀某些篇章時多讀幾遍。不過，考慮到丹內特那種明晰、詼諧以及充分為讀者考慮而不使用術語的文風所帶來的智力上的滿足，多讀幾遍才能讀懂正是本書的一大特色，而不是一個瑕疵。
