I've been neglecting this blog lately. Instead of posting, I've been spending my rare spare time exploring multiple interests. Specifically, clojure, data science, and quantitative investing.
I'm hoping to combine these interests and post about them in the near future.
The Cuckoo's Egg Tracking: a Spy Through the Maze of Computer Espionage by Cliff Stoll
In 1986, Cliff Stoll's boss asked him to investigate a $0.75 accounting error for the use of their lab's computer. He quickly discovered that a hacker had penetrated their computer system and was attempting to do the same to the Milnet computers it was connected to. The situation quickly cascaded into a multi-national search for a malicious hacker-spy involving multiple "three letter" government agencies. At the center of it all was Cliff, an astronomer turned system administrator turned digital sleuth. In The Cuckoo's Egg, Cliff provides a detailed account of his adventure and eventual success.
I really enjoyed The Cuckoo's Egg. Although I was vaguely aware of the story, I only recently learned of the book. I was immediately hooked and struggled to put it down.
The Cuckoo's Egg provides a detailed description of 1980's computing, a subject for which I have an irrational fondness. It's a great reminder of how innocent a time that was and how far technology has come.
Timeless, though, were Cliff's creativity and persistence. I wish more people today put as much effort into solving problems, even apparently small ones. Cliff's story remains an inspiration.
Cliffs political retrospection added an unexpected dimension to the story. His initial mental model of government agents was comic book-esque. During the pursuit, he gradually realized that they were just normal people with similar values. Cliff's willingness to alter his political views was also encouraging.
PDF versions of the book are available online. The book was also summarized in the NOVA episode The KGB, The Computer, and Me albeit without much of the detail that made the story interesting.
If you like computer history, cyber-security, and mystery stories then you will likely enjoy The Cuckoo's Egg.
Fermat's Enigma by Simon Singh
In 1637, Pierre de Fermat, a renown amateur-but-genius mathematician, was reading Diophantus's Arithmetica and wrote the following margin note:
I have discovered a truly marvelous proof that it is impossible to separate a cube into two cubes, or a fourth power into two fourth powers, or in general, any power higher than the second into two like powers. This margin is too narrow to contain it.
In other words, although there are many three integer solutions to Pythagoras's Theorem,
X^2+Y^2=Z^2
There are no three integer solutions for higher powers,
X^3+Y^3=Z^3 X^4+Y^4=Z^4 ....
Unfortunately, no written record of Fermat's proof has ever been found. Worse, Fermat had a reputation for pranking his fellow mathematicians by claiming to have secretly solved impossible problems. For 350 years, it was uncertain if a proof ever existed. But that didn't stop a lot of people from trying, including some of the best mathematicians in history.
In this book, Simon Singh provides a thorough account of the many efforts to prove Fermat's Last Theorem. Particular attention is given to Andrew Wiles's successful solution in 1994, the result of a seven year solitary effort that shocked the mathematics world.
The book is structured very well. Singh expertly interweaves the history and mathematics behind Fermat's conjecture in an easy to understand and engaging manner. Singh describes the complicated mathematics involved just enough to appreciate Wiles's solution without going into too much detail. The narrative flows evenly and holds the reader's attention well.
Wiles's story is incredible. He was first fascinated by Fermat's Last Theorem as an adolescent. After earning a PhD in mathematics, Wiles found himself uniquely positioned to pursue a proof. He made the bold decision to both work in secret and devote all of his time to developing a proof. For seven years, Wiles worked night and day in isolation until he finally succeeded. After a fatal flaw was found during peer review, he spent an additional year fixing the proof. Wiles's focus, dedication, and determination are truly inspiring.
Fermat's Last Theorem is great book if your into math, history, and solitary geniuses overcoming the odds.
Each day, I come across numerous web articles, blog posts, newsgroup posts, etc, that appear interesting. Often, I discover them while working on another task. To avoid distraction, I typically save their links for later review. Sometimes I drag the links to my desktop. Sometimes I bookmark them in my browser. Sometimes I send them to myself via email. Sometimes, I post them to my delicious account. It's time to admit that I need a better process.
In a prior post, I mentioned that I use Emacs's org-mode to organize
my notes and tasks. I recently setup org-mode's Capture capability to
easily record the deluge of thoughts that come at random throughout
the day. While reading the documentation, I discovered the solution to
my link saving woes, org-protocol. In particular, the ability to
capture links to an org file directly from a web browser as
demonstrated in this screencast.
Imitating the screencast on OS X turned out to be harder than I expected. So, I thought it worth wile to post my approach.
To begin, it's worthwhile to understand how org-protocol captures
work. org-protocol is based on Emacs server which allows
applications to use Emacs for text editing. A common practice is to
have shells use an already running Emacs instance rather than starting
a new one. This is accomplished by a helper program, emacsclient, that
communicates with the primary Emacs instance. For org-protocol
captures, emacsclient is launched with a specially formatted
argument.
emacsclient org-protocol:/capture:/tname/http://foo.com
By advising the server-visit-files function, org-protocol detects
such arguments and creates org-mode entries from them. A powerful
template facility is provided to specify how the argument information
is transformed into an org entry. Multiple templates are supported and
selected by the argument's tname field. The remainder of the
argument specifies the URL, in this case http://foo.com, and an
optional note (not shown in the example).
Templates are specified by elisp code like the following,
(setq org-capture-templates
'(("tname" "Link" entry
(file+headline org-default-notes-file "Links to Read")
"* %a\n %?\n %i")))
This template, called tname, tells org to save the entry in the
default notes file under the header "Links to Read" with the url as a
sub-heading. This results in something like,
* Links to Read ** http://foo.com
See the Emacs documentation for all of the template facility's capabilities and options.
In the screencast, two "tricks" are used to have FireFox call
emacsclient with the argument needed to capture the present page.
The first is a bookmarklet that creates the appropriate emacsclient
argument,
javascript:location.href='org-protocol://capture://tname/'+ encodeURIComponent(location.href)+'/'+ encodeURIComponent(document.title)+'/'+ encodeURIComponent(window.getSelection())
The second trick takes advantage of the fact that the emacsclient
argument is formatted as a URI. The topmost component of a URI is
called the URI scheme. The standard scheme, http, represents HTTP
hyperlinks and is handled directly by the browser. Many other URI
schemes exist and most browsers support launching separate programs,
sometimes called URI handlers, to process them. In the screencast,
FireFox is configured to launch emacsclient when links with the
org-protocol scheme are "clicked".
Duplicating this functionality with Safari on OSX turned out to be
harder than expected. In an effort to make things easy, OSX provides
the Launch Services API to automate the registration of URI schemes
and their handlers. Unfortunately, a manual method isn't provided to
specify new URI schemes and handlers. This means Safari can't simply
be told to launch emacsclient when org-protocol links are
"clicked".
While searching for a solution, The worg website led me to the
org-mac-protocol project. Although promising, org-mac-protocol uses
AppleScripts executed via a drop down menu. Call me lazy but I really
like the bookmarklet approach. org-mac-protocol also provides far
more functionality than I was interested in. I like to keep things
simple.
A second look at the Launch Services documentation revealed that two mechanisms are provided to register URI schemes and handlers. Using a programmatic API, applications can, at execution time, register themselves as the handler for new URI schemes. Alternatively, applications can include the URI scheme and handler information in their application bundle property list. Of the two approaches, the property list approach looked like the best to pursue.
Property lists are used by OSX to store application and user settings. They're essentially Objective-C objects serialized to XML. Every OSX application contains a default property list in its application bundle that the Finder reads after certain events. While processing property lists, the Finder will register any URI schemes and handlers it finds with Launch Services. With this approach, all that is necessary to register a new URI scheme and handler is to edit an XML text file.
Unfortunately, modifying Emacs's application bundle plist didn't
seem to be an option. I didn't see a way to specify the helper program
emacsclient as the URI handler.
I knew from prior experience that AppleScripts can be packaged as
application bundles. I reasoned that I could write an AppleScript to
launch emacsclient, save it as an application bundle, and modify its
property list to register the script as a handler for org-protocol
URIs. I suspected that this had been done before and a quick google
search led me to this stackoverflow thread.
Using AppleScript Editor and the stackoverflow thread as an example, I
wrote the following script and saved it as an application bundle
called EmacsClientCapture.app.
on open location this_URL
do shell script
"/Applications/Emacs.app/Contents/MacOS/bin/emacsclient "
& this_URL
end open location
Next, I edited the script's plist at the path,
EmacsClientCapture.app/Contents/Info.plist
And added the following XML elements just before the final
</dict></plist> tags.
<key>CFBundleIdentifier</key> <string>com.mycompany.AppleScript.EmacsClientCapture</string> <key>CFBundleURLTypes</key> <array> <dict> <key>CFBundleURLName</key> <string>EmacsClientCapture</string> <key>CFBundleURLSchemes</key> <array> <string>org-protocol</string> </array> </dict> </array>
I then moved the application bundle to the /Applications directory.
This caused the Finder to read the property list and register
EmacsClientCapture with Launch Services as the handler for the
org-protocol URI scheme.
I added the bookmarket described above to Safari and viola! I can now click on the bookmarklet and save a link to the current page in an org-mode file. No more disorganization. Of course, it's now easier to collect distractions but that is a problem for a future post.
On Writing Well by William Zinsser
Clarity. Simplicity. Brevity. Humanity. Those are the four attributes of good writing that Zinsser promotes and teaches in this classic book on writing.
The book is structured into four parts. Part one, Principles, covers fundamental topics like simplicity, clutter, style, words, and usage. In part two, Methods, Zinsser teaches how to structure a coherent story. Part three, Forms, provides advice on writing interviews, travel stories, technical articles, business communications, and other types of writing. Part four, Attitudes, discusses common feelings and decisions during the writing process. Throughout the book, Zinsser uses examples to illustrate and reinforce his points.
I really liked this book and agree strongly with Zinsser's values. A lot of modern writing is long-winded, complex, and content-free. Simple and clear writing is not only more effective but also more enjoyable. I've always tried to use a simple, direct writing style. I'm eager to apply the book's advice to further improve my writing.
I was greatly encouraged by many of Zinsser's comments on the writing process itself. For example, I consider myself a slow writer. I often spend a lot of time revising my writing to get it "just right". Even simple things like emails and blog posts seem to take an excessive amount of time. I frequently feel insecure about this so I was glad to read the following,
Writing is hard work. A clear sentence is no accident. Very few sentences come out right the first time, or even the third time. Remember this in moments of despair. If you find that writing is hard, it's because it is hard.
Similarly, I was inspired by the following comment in the chapter "Enjoyment, Fear, and Confidence",
Living is the trick. Writers who write interestingly tend to be men and women who keep themselves interested. That's almost the whole point of becoming a writer. I've used writing to give myself an interesting life and a continuing education. If you write about subjects you think you would enjoy knowing about, your enjoyment will show in what you write. Learning is a tonic.
I started this blog to learn by writing about my many interests. I find that explaining a topic often leads to deeper insights. I hope that writing and blogging will help me to continue learning and leading an interesting life.
The "Thoughts about thinking" post motivated me to improve my brain fitness. To that end, I found the following three talks very informative.
I really appreciate Google posting internal guest lectures to YouTube and GoogleVideo. I have watched many of the computer science talks and learned a lot. It's nice to know that talks on many other valuable topics are also available.
I once learned a valuable lesson - never do well a task that you don't want to do again.
The situation started out innocently. A task for the project I was working on needed to get done. I disliked the task but grudgingly did it for the benefit of the team. I did my best to do the task well with the expectation that I would be rewarded with more enjoyable work. Instead, I was asked to keep doing it. I protested unsuccessfully and was soon miserable. I couldn't understand how acting selflessly and doing a good job led to such "punishment".
I discovered that when you do any job well the benefiters want you to keep doing it. If they're confident you'll produce good results, they would rather encourage you than find a replacement (who may not do as well). I eventually realized that I shouldn't have done a good job in the first place.
Initially, I found this insight disturbing. As a child, I was taught to always do my best at everything. As I grew up, I tried to do my best at school, sports, hobbies, and part-time jobs. Gradually, "always doing my best" became a core attribute of my self-image. Therefore, the notion of consciously doing less than my best just seemed wrong.
Then I made a discovery - some of my role models consciously do or did less than their best to avoid undesirable work.
For example, the legendary physicist Richard Feynman discusses "actively acting irresponsible" in this BBC interview. He also cautioned against administrative roles in this letter to Stephen Wolfram. Donald Knuth and Neal Stephenson are well known for being "bad" at correspondence. On a somewhat related note, Paul Graham warns in this essay against distracting thoughts and activities. More personally, some of my mentors have privately admitted to performing badly at tasks that they don't want to do.
From these examples I've formulated the following three guidelines:
Following guidelines 1 and 2 will hopefully provide more time for pursuing guideline 3. The ideal result is to be so highly valued for doing work you enjoy that you won't get asked to do anything else - the opportunity cost for distracting you will be too high.
For myself, I expect a lot of time and practice will be required to put these guidelines into consistent application. After all, a self-image can be hard to change. Thankfully, I have role models to encourage me.