人一日未找到，自己的無限旅程，一日都會很難過。
— Me@2012.02.05
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2012.02.07 Tuesday (c) All rights reserved by ACHK
Monthly Archives: February 2012
避免犯錯
這段改編自 2010 年 5 月 25 日的對話。
避免犯錯的方法是，在平時先錯一次。
那樣，考試時，你就不會再犯同一個錯誤。
— Me@2012.02.07
2012.02.07 Tuesday (c) All rights reserved by ACHK
Reductionism 2
Holism
Holism is the idea that natural systems (physical, biological, chemical, social, economic, mental, linguistic, etc.) and their properties, should be viewed as wholes, not as collections of parts. This often includes the view that systems somehow function as wholes and that their functioning cannot be fully understood solely in terms of their component parts.
Reductionism is sometimes seen as the opposite of holism. Reductionism in science says that a complex system can be explained by reduction to its fundamental parts. For example, the processes of biology are reducible to chemistry and the laws of chemistry are explained by physics.
— Wikipedia on Holism
2012.02.06 Monday ACHK
存在先於本質
Batman Begins, 2
本質先於存在
我在買零件組裝電腦前，心目中，會對那部電腦的性能有所要求，例如它的運算速度有多高。換句話說，那部電腦在存在之前，就已經擁有自己的性質。那就為之「本質先於存在」。
— Me@2012.02.06
存在先於本質
其最著名和最明確的倡議，是沙特的格言：「存在先於本質」。他的意思是，除了人的生存之外，並沒有天經地義的道德或靈魂。道德和靈魂，都是人在生存中創造出來的。人沒有義務遵守，某個道德標準或宗教信仰，卻有選擇的自由。要評價一個人，就要評價他的所作所為，而不是評價他是個什麼人物，因為一個人，是由他的行動來定義的。
— 改編自《維基百科》
2012.02.06 Monday (c) All rights reserved by ACHK
凝固文章
種子論起點 10.3.2 | 網誌時代 12.3.2 | 專家博士（製作特輯）3
這段改編自 2010 年 3 月 20 日的對話。
每次寫文章時，我會採取「最低消費」策略：在文章內容的發展上，見步行步，行步見步。
每次聽錄音，抄錄自己的對話時，只要「集齊」一個要點，我就會停筆，立刻發表。該篇文章之後的「劇情」如何發展，我會暫時置之不理。我不會刻意去理會，未來的文章，會與手頭上的文章，將會如何互動。
那樣做，就可以化解了剛才所提，寫文章的兩大難題：
寫文章雖然有趣，但同時令人厭惡。每次寫得越少，厭惡的程度就會越細。
一篇文章的思考單位越多，就越難組合得正確而優美。如果每篇也只有一個主要的思考單位，就容易組合得多，因為根本毋須「組合」。有時，解決問題的最好方法是，令自己根本毋須解決那個問題。
另外，一篇文章發表以後，我就不會再修改，除非有明顯的錯別字。如果事後發現有嚴重的思想漏洞，我會索性把該篇文章刪除。
每一篇文章，我也視之為最後的一個版本。人生苦短，假設我每日寫一篇文章，一生人就只可以寫到三萬多篇。與其留戀舊文章，倒不如，花那些時間去創作新文章，傳播新思想。
額外的好處是，凝固已寫的文章，一方面，往後的文章不會被它「滋擾」：寫新文章時，我毋須考慮，那些新思想，對舊文章有什麼影響，因為，我根本不打算去修改它。
另一方面，文章一凝固了，就可以化身成，往後文章的基礎：每一篇文章的內容，會自動成為下一篇內容的種子。每一篇的終結，會自動成為下一篇的起點。
— Me@2012.02.06
2012.02.06 Monday (c) All rights reserved by ACHK
Index notation
Symmetries are the result of a redundant, but useful, description of a theory.
In fact, one of the main uses of index notation is just to manifest the symmetry.
— Fields
— Warren Siegel
Siegel authored an extensive (885pg) textbook called Fields, now in its 3rd edition. It is notable in that it follows a very modern approach and incorporates many topics (including string theory) not found in other field theory textbooks. He advocates a “symmetry-based” approach and uses this in his Quantum Field Theory I&II classes. The textbook is also notable in that it is completely an “electronic book” and can be downloaded for free from Siegel’s website.
— Wikipedia on Warren Siegel
2012.02.05 Sunday ACHK
Recursion 8.2
I am a Strange Loop, 3.2
When I am conscious, different times of myself-s interact.
When different times of the same (software) object interact, there comes consciousness.
The past is part of the present.
So consciousness comes from the whole-part interaction.
— Me@2012-01-24 11:03:37 AM
2012.02.05 Sunday (c) All rights reserved by ACHK
Uncertainty principle, 5
Universal wave function, 12
The uncertainty principle states the limit of reductionism. Science is based on reductionism, which assumes we can investigate part of the universe. So the uncertainty principle, in effect, states the limit of science.
— Me@2011.11.29
2012.02.05 Sunday (c) All rights reserved by ACHK
Process, not a state, 4
Excellence is an art won by training and habituation. We do not act rightly because we have virtue or excellence, but we rather have those because we have acted rightly. We are what we repeatedly do. Excellence, then, is not an act but a habit.
— Aristotle (384 BC – 322 BC) Greek Philosopher
* Source: Will Durant, _The Story of Philosophy: The Lives and Opinions of the World’s Greatest Philosophers_ (1926) [Simon & Schuster/Pocket Books, 1991, ISBN 0-671-73916-6] Ch. II: Aristotle and Greek Science; part VII: Ethics and the Nature of Happiness:
“Excellence is an art won by training and habituation: we do not act rightly because we have virtue or excellence, but we rather have these because we have acted rightly; ‘these virtues are formed in man by his doing the actions’; we are what we repeatedly do. Excellence, then, is not an act but a habit: ‘the good of man is a working of the soul in the way of excellence in a complete life… for as it is not one swallow or one fine day that makes a spring, so it is not one day or a short time that makes a man blessed and happy‘” (p. 76).
The quoted phrases within the quotation are from the Nicomachean Ethics, Book II, 4; Book I, 7. The misattribution is from taking Durant’s summation of Aristotle’s ideas as being the words of Aristotle himself.
— Wikiquote
Excellence is a process, not a state, nor an event.
An event is a change of state. A process is an infinite chain of events.
— Me@2011.01.01
— Me@2012.02.04
2012.02.04 Saturday (c) All rights reserved by ACHK
種子論起點 10.3.1
網誌時代 12.3.1
這段改編自 2010 年 3 月 20 日的對話。
我不會好像 Paul Graham 那樣，先寫一篇長文章，然後，再花幾個星期的時間，去不斷修改打磨。我不喜歡那個方法。
寫作，是一項麻煩而沉悶的工序。寫長文章，就即是要在一斷連續的長時間內，處於「寫作」的狀態。我會感到非常厭惡。如果我企圖寫長文章的話，我根本會抗拒到，從來不會開始寫。
寫長文章的麻煩，在於文章一長時，很難可以同時做到，結構嚴謹、內容一致 和 思路清晰。困難的地方，在於一篇文章的複雜程度，會以幾何級數，隨長度而增長。例如，假設「文章乙」的長度，是「文章甲」的兩倍。那樣，「文章乙」的複雜度，隨時會是「文章甲」的四倍。「寫程式」有類似的原理。
所以，我通常也只會寫短文章。每次寫文章時，我會採取「最低消費」策略：在文章內容的發展上，見步行步，行步見步。
— Me@2012.02.04
2012.02.04 Saturday (c) All rights reserved by ACHK
Exponential delay
We also have some new features to prevent flamewars. The most conspicuous is an exponential delay before reply links appear on deeply nested comments. We’d noticed these were rarely the most interesting comments on the site. We’re hoping that instead of killing stupid arguments, it will be sufficient to apply gradually increasing drag to them.
— 29 Apr 2009: Faster, Fewer Flamewars
— Paul Graham
2012.02.03 Friday ACHK
Life hacking 3
Life is a process of finding exceptions.
— Me@2011.11.15
— Me@2011.12.11
2012.02.03 Friday (c) All rights reserved by ACHK
Probability 2.4
這段改編自 2010 年 5 月 25 日的對話。
我現在示範一下，如何寫你的那本「魔法筆記」。
第一句：
「P 方法」和「S 方法」的整體意義相同，因為它們是用來計同一道機會率題目的。如果你的運算無誤，它們的答案，會是相同的數值。
第二句：
但是，「P 方法」和「S 方法」的細節不同，因為「P 方法」的分子，並不是「S 方法」的分子；「P 方法」的分母，亦不是「S 方法」的分母。
第三句：
考試時，「P 方法」和「S 方法」中，你先選定其中一個，用來作答。然後，在草稿紙上，再用另一個方法，以作驗算。
第四句：
（這一點是額外的，可以不寫。）在「P 方法」中，分子和分母都是 permutation（排列）。而在「S 方法」中，分子和分母都是 combination（組合）。
第五句：
在「P 方法」中，分子和分母都是 permutation（排列），重視次序。但是，根據這一題的描述，次序並不重要。或者說，題目所要求的，是 combination（組合）。即使是次序不同，凡是「兩紅兩黑」的排列，你都要採納。那樣，有多少個排列，都符合「兩紅兩點」的規定呢？
4C2 （即是 「4 選 2」，等於 6。）
所以，在「P 方法」中，在四個「機會率分數」之後，你要再乘以一個「4C2」。
即使是個別的要點，你也未必可以立刻明白。更何況，若要保證自己的機會率運算正確，你要每一點也理解清楚。一般人也不能做到。千萬不要做一般人。
— Me@2012.02.03
2012.02.03 Friday (c) All rights reserved by ACHK
Hyperthymesia
Hyperthymesia, also known as piking or hyperthymestic syndrome is a condition in which the individual possesses a superior autobiographical memory, meaning they can recall the vast majority of personal experiences and events in their lives.
Defining characteristics
Individuals with hyperthymesia can recall almost every day of their lives in near perfect detail, as well as public events that hold some personal significance to them. Those affected describe their memories as uncontrollable associations, when they encounter a date, they “see” a vivid depiction of that day in their heads. Recollection occurs without hesitation or conscious effort.
It is important to draw a distinction between those with hyperthymesia and those with other forms of exceptional memory, who generally use mnemonic or similar rehearsal strategies to memorise long strings of subjective information.
— Wikipedia on Hyperthymesia
2012.02.02 Thursday ACHK
Apple seed
Like an apple hanging from a tree I picked the ripest one I still got the seed.
— Thinking Of You
— Katy Perry
（以下不是原著的意思，因為我根本不明白，原著是什麼意思。）
即使我拿下的，是蘋果樹上最差的一個蘋果，我仍然可以得到，那棵蘋果樹的種子。
— Me@2012.02.02
2012.02.02 Thursday (c) All rights reserved by ACHK
種子論起點 10.2
網誌時代 12.2 | 程式員頭腦 12.2
這段改編自 2010 年 3 月 20 日的對話。
你留意一下，我文章的結構，和電腦程式極為相似。
我每一篇文章，就好像一個「大程式」內的一個「小 function」（子程式）。一個「子程式」的特性是，一方面，它本身會有特定的一個完整功能；另一方面，它亦可以被「主程式」利用，與其他「子程式」合作，執行大任務。
同理，我盡量做到，每篇網誌文章「至少有一個意念」和「至多有一個意念」。那樣，我每篇文章就可以各自成篇，自成一國。讀者閱讀我任何的一篇文章，就可以立刻得益，而毋須同時閱讀其他。
另一方面，如果你一次過閱讀，連續幾篇標題相同的文章，你會發現，它們會合體，變成一篇大文章。在一個額外的上文下理中，你或者會有新的體會。
— Me@2012.02.02
2012.02.02 Thursday (c) All rights reserved by ACHK
Digital physics, 2
The last decade in theoretical physics has simply settled this question – whether someone likes it or not – and the answer is “No”. The spacetime geometry cannot be fundamental at the Planck scale. It is subject to transitions, dualities, and holography, among other phenomena that prove that it must be flexible and it cannot arise from a graph because a graph is too local. In neither of the existing descriptions we can find a discrete spacetime and it seems rather unlikely that there exists a description where it is discrete.
— Quantum Graphity
— Lubos Motl
2012.02.01 Wednesday ACHK
The Neverending Story
Only reality can be a neverending story.
— Me@2012.01.27
2012.02.01 Wednesday (c) All rights reserved by ACHK
Probability 2.3
這段改編自 2010 年 5 月 25 日的對話。
在完全熟習 P 方法和 S 方法之前，為免干擾自己的思考，最好不要研究，它們為何可以針對同一題題目，而得到同樣的答案。
在完全熟習之後，如果想研究一下，可以用這個提示：
在 P 方法中，分子和分母都是 permutation（排列）。而在 S 方法中，分子和分母都是 combination（組合）。
— Me@2012.02.01
2012.02.01 Wednesday (c) All rights reserved by ACHK
Physics Town 