Monthly Archives: December 2012

Dear Esther

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To get a feeling of dying, play the video game Dear Esther till the end.

— Me@2012.12.16

When you finish a video game, you go back to the real world;

when your real world is over, you go back to your realer world.

— Me@2012.12.21

There is another theory, that in a car crash, Esther was put in a coma, and the voice is her husband talking to her, in hopes that she can hear him. She wanders along beaches and through caves that are filled with sometimes strange things, things that are bits and fragments of what she is hearing and what her mind is putting together. At the end when Esther jumps, it is possible her heart rate increased, showing up on the hospital monitor, which would explain the voice at the end saying “Come back,” and the darkness at the end would probably be her dying in the coma.

— Wikipedia on Dear Esther

— 21:01, 29 May 2012

2012.12.22 Saturday (c) All rights reserved by ACHK 

Past papers 26.1

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這段改編自 2010 年 6 月 15 日的對話。

我先給功課你們。你想拿什麼 grade（成績等級）？

（LMC：可以拿什麼 grade？）

如果要拿到 A 級成績，你就要做足，總共 20 年的 past papers（歷屆試題）。

（CPK：吓？你要我們下次見面前，完成 20 年的 past paper？）

當然不是。我要計一計，你們應哪一年的 past paper 開始做。你們將在 2011 年參加高考。倒數 20 年，即是你應該大概由 1990 年的那一份，開始操練。那你們在下次見我時，就要遞交完成了的 1990 年 past paper。

你練習 past paper 時，記住要「計時間、計分數」，然後還要做改正，記低需要背誦的重點，於「魔法筆記」之中。不懂改正的地方，就正正是下次問我的問題。

— Me@2012.12.22

2012.12.22 Saturday (c) All rights reserved by ACHK

Quantum entanglement 2

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EPR paradox, 7

Some people have interpreted this as telling us that “everything is connected to everything else” or that “quantum mechanics entangles us all in one universal whole.”

After all, the reasoning goes, at the big bang everything emerged from one place since, we believe, all places we now think of as different were the same place back in the beginning.

— p.122

— The Fabric of the Cosmos

— Brian Greene

2012.12.22 Saturday ACHK

變通

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Easy 3

“Easy” in Chinese is “容易”, literally meaning “able to change“.

— Me@2012-11-29 10:47:38 AM

It is not the strongest of the species that survives, nor the most intelligent, but rather the one most adaptable to change.

— Charles Darwin misquotation

The definition of insanity is doing the same thing over and over and expecting different results.

— Albert Einstein misquotation

If you are willing to change based on the feedback from the reality, many difficult things will become easy.

— Me@2012.12.17

易，窮則變，變則通，通則久。

— 系辭下

— 易經

2012.12.21 Friday (c) All rights reserved by ACHK

SICM, 2

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這段改編自 2010 年 4 月 3 日的對話。

《SICM》（Structure and Interpretation of Classical Mechanics）總共花了我兩年的時間。我大概由 2006 年，閱讀至 2008 年。除了閱讀課文外，我還把內裡的幾乎所有練習，無論是數學題，還是程式題，都一一擊破。要花那麼長的時間才能完成，主要是因為上班的工務繁忙。每日可以花在自修的時間，通常也不會超過半小時。

雖然時間成本奇高，但是，我仍然覺得是值得的。一來，它是一本名著，質素非常高。二來，它竟然把我人生的兩大興趣，重疊在一起。

— Me@2012.12.21

2012.12.21 Friday (c) All rights reserved by ACHK

For all

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Universe 2.1

“All” is “所有” in Chinese. Literally,

all = 所有 = the place has

The definition of word “universe” is “everything” or “all the things“. 

universe = all the things

However, this definition is not 100% sharp, because the meaning of “all” is relative to a list or a place. In order to give a meaning to the word “all“, you have to provide a list or a place in the sentence it appears.

When referring to a list, for example, the meaning of the phrase “all of A, B, and C” is the same as “A, B, and C“.

all of A, B, and C  =  A, B, and C

However, the definition of “universe” does not specify a list, such as

universe = all of A, B, and C

When referring to a place, for example, the meaning of the phrase “all the people in this house” is:

You keep looking for people in this house. Whoever you can find, include him or her onto your list of people. Once you cannot find new people in the house anymore, your list will have “all the people in this house“.

In other words, in order to give the word “all” a meaning, you have to provide a range for searching. However, the definition of “universe” does not specify a place, such as

universe = all the things in X,

unless we define the word “universe” as

universe = all the things in universe

However, this is a circular definition.

— Me@2012.10.16

— Me@2012.12.11

— Me@2012.12.20

2012.12.21 Friday (c) All rights reserved by ACHK

程式員頭腦 14.3

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SICM, 1.3

這段改編自 2010 年 4 月 3 日的對話。

即使有時會剛巧得到正確的結果，但是由於胡亂推導，大家也不知道，那個正確結果的真正由來。所以，每一代的學生，都不可能明白那一個部分。

要戒除「暗地裡轉換意思」的陋習，並不困難。如果透過編寫程式，來解決力學問題，你就要先把那個力學問題，翻譯制訂成電腦程式的版本。那樣，在過程中，你自然會百分百釐清了，所有符號的意義，因為，在同一個程式中，同一個符號，電腦只會容許，有唯一的一個意思。電腦不會讓你（，在沒有事先特別聲明的情況下），任意放大、縮小 或 更改，那一個符號的意思。電腦不會錯失，你任何的「概念扭曲」或者「概念滑轉」，所以不會有絲毫的容忍。

由於要你「寫程式學力學」，《SICM》（Structure and Interpretation of Classical Mechanics）會教你一種編程語言 Scheme programming language。這種語言的好處是，你學了一句後，就可以立刻應用那一句，而不像一般的程式語言，應用前，要先行學習一大堆語法。

（安：那本書真的用 programming（電腦編程），來講解 mechanics（力學）？）

無錯。正如一般的教科書，課文以外，《SICM》還有例題和練習題。而例子和練習之中，有超過一半是程式題目。其餘的則是文字題目和數學題目。

但是，《SICM》的正題始終是力學，而不是寫程式。正如，力學需要用數學。但是數學在這本書內，只是工具，不是主菜。

— Me@2012.12.18

2012.12.19 Wednesday (c) All rights reserved by ACHK

EPR paradox, 6

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The claim that EPR effects violate the principle that information cannot travel faster than the speed of light have been countered by noting that they cannot be used for signaling because neither observer can control, or predetermine, what he observes, and therefore cannot manipulate what the other observer measures.

— Wikipedia on Copenhagen interpretation

2012.12.17 Monday ACHK

Writer’s block 5

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種子意念 7

ars 304 days ago | link

Isaac Asimov and Piers Anthony have both written in their books that they never suffer from writers block, and the reason both gave is that they read and reply to letters from their audience. Isaac Asimov especially replied to every single letter he received (I’m not sure about Piers Anthony).

Penn and Teller seem to have the same idea: Interact with every member of your audience who wants to talk to you. And they are one of the most successful magicians.

I think everyone should learn from this. Do you write a blog? Read every single comment you get, and reply to as many as you can. Run a business? Read as much customer service mail as you can. And if you are small read ALL of it.

— 14 years ago: the day Teller gave me the secret to my career in magic

— Hacker News

2012.12.17 Monday ACHK

概念滑轉

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SICM, 1.2 | 程式員頭腦 14

這段改編自 2010 年 4 月 3 日的對話。

“In almost all textbooks, even the best, this principle is presented so that it is impossible to understand.” (K. Jacobi, Lectures on Dynamics, 1842-1843). I have not chosen to break with tradition.

— V. I. Arnold, Mathematical Methods of Classical Mechanics, footnote, p. 246

— Structure and Interpretation of Classical Mechanics

這本書的主要好處是，它會要求你，透過編寫簡短的電腦程式，來解決力學問題。反過來說，你亦可以透過解決力學問題，來練習 programming（電腦編程）。

這本書的主旨是，在經典力學，人們做公式推導的過程中，有時會把一些數字符號的意思，不自覺地改了一點，導致推導失效。例如，運算步驟的第二行和第五行，都會出現的函數 f 這個符號。但是，第二行的 f ，是代表 f(x,y)。而第五行的 f ，卻是指 f(x(t),y(t))。

即使有時會剛巧得到正確的結果，但是由於胡亂推導，大家也不知道，那個正確結果的真正由來。所以，每一代的學生，都不可能明白那一個部分。

如果透過編寫程式，來解決力學問題，你就可以避免了「暗地裡轉換意思」的陋習，因為在同一個程式中，同一個符號，電腦只會容許，有唯一的一個意思。電腦不會錯失，你任何的「概念扭曲」或者「概念滑轉」，所以不會有絲毫的容忍。

— Me@2012.12.17

2012.12.17 Monday (c) All rights reserved by ACHK

Design and Research

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意念可樂 3

A good scientist is a person with original ideas. A good engineer is a person who makes a design that works with as few original ideas as possible. There are no prima donnas in engineering.

— Disturbing the Universe

— Freeman Dyson

handrake 2 days ago | link | parent

I think MS was pretty much the same way until very recent. Maybe companies really start making money when they stop being innovative.

— Amazon Has the Most Generous Shareholders in the World

— Hacker News

The difference between design and research seems to be a question of new versus good. Design doesn’t have to be new, but it has to be good. Research doesn’t have to be good, but it has to be new.

I think these two paths converge at the top: the best design surpasses its predecessors by using new ideas, and the best research solves problems that are not only new, but actually worth solving. So ultimately we’re aiming for the same destination, just approaching it from different directions.

— Paul Graham

2012.12.17 Monday ACHK

基礎問題

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這段改編自 2010 年 6 月 8 日的對話。

有時，越「簡單」的問題，反而越難解答。例如，如果有一名小孩問你，為何「3 乘 2 等如 6」，你可以答，因為

3 x 2 = 3 + 3 = 6

但是，如果他問你，為何「1 + 1 = 2」，你又好像不知從何回答。

（CSY：我曾經答，因為一個蘋果加另一個蘋果，等如兩個蘋果。但是，發問者又質疑，那兩個蘋果並不是完全一樣，為何可以將它們加在一起？）

— Me@2012.12.16

2012.12.16 Sunday (c) All rights reserved by ACHK

Nothingness

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Nothing is better than having a good wife. 

Having a toothbrush is better than having nothing.

—

Therefore, having a toothbrush is better than having a good wife.

Nothing is better than having a good wife. 

{} > {good wife}     (wrong)

{x : x > good wife} = {}     (correct)

Having a toothbrush is better than having nothing.

{toothbrush} > {}

The is‘s have two different senses here. The first “is better than” is for comparing objects. The second “is better than” is for comparing sets. An object and a meta-object should not be put together for comparison.

— Me@2012-04-02 10:46:22 AM

2012.12.15 Saturday (c) All rights reserved by ACHK

SICM

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這段改編自 2010 年 4 月 3 日的對話。

（安：我怎樣把 mechanics（力學）學得好一點？）

哪一門力學？經典力學，還是量子力學？

（安：經典力學。）

你想應用在哪些地方？

（安：暫時純粹為了求知和娛樂。）

那我介紹一本名著給你。它叫做《SICM》（Structure and Interpretation of Classical Mechanics）。它免費發布於 MIT（麻省理工學院）的網站。

這本書的主要好處是，它會要求你，透過編寫簡短的電腦程式，來解決力學問題。反過來說，你亦可以透過解決力學問題，來練習 programming（電腦編程）。

— Me@2012.12.15

2012.12.15 Saturday (c) All rights reserved by ACHK

Universe

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exists = is in = belongs to = can be found

“Exists” is “存在” in Chinese. Literally,

exists = 存在 = is stored in

“X is stored in” is not a complete sentence because it lacks an object. X is stored in where?

Existence is asking for an address. If you know something exists, but do not know in which it is stored, you can always say “X is in the universe“. The concept “universe” acts as a universal address or universal container. 

But by definition, the universe itself cannot have any address. So the sentence “the universe exists” is meaningless.

— Me@2012.10.18

2012.12.14 Friday (c) All rights reserved by ACHK

心懷混亂

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這段改編自 2010 年 4 月 3 日的對話。

I tell you: one must have chaos within oneself, to give birth to a dancing star.

– Friedrich Nietzsche

我覺得「種子論」這個名稱，翻譯得很好。「種子論」既沒有資料內容上的漏洞，亦沒有教學表達上的缺憾。

（安：李教授都時常用「種子」做比喻。例如，他會講「功夫種子」。有些做人道理，會因為你的年紀太小，學了也不完全明白。你只會知其大概，而不會立刻真切感受到，那些道理的深刻意思。但是，即使只知其大概，也應該不斷學，因為二十歲學了的道理，其實是「功夫種子」。假以時日，它們就會發芽。　　　

到二十八歲時，你會「突然」明白一些，意想不到的道理，令你想通了大部分人生問題，化解了大部分心靈死結。自此，你再不會時常心緒不寧。

那顯示了，你二十歲時，努力埋下的一大堆伏線，終於修成正果。那亦同時顯示了，在心理上，你年華已去，不再年青。你再不會像以往一樣，時常若有所思，激烈爆發創意。）

— Me@2012.12.12

人們必須在心中懷著混亂，為了能夠創造一個舞動的新星。

– 尼采

2012.12.12 Wednesday (c) All rights reserved by ACHK