wordwolf posted this a couple years ago. I read it again and decided it was worth more thought.

All truly great revolutions occur outside the circle. They are usually brought about by great and quiet people working hard for many years in quiet rooms. Everyone else just rides the wave, or runs from it. You will be the wave.

You're right about relevance. True relevance is timeless. What you felt [...] is a highly evolved form of peer pressure. Every professional circle has it. Its movers and shakers, its gossip columns, its lists of who's in and who's out. Ignore the crowd. The crowd fears history because history judges true worth. Dream, then think, then do. History will judge in your favour.

He's all over the Health section of Google News today. Experimental Cancer Therapy Stops Man's Melanoma at WebMD; also see the BBC, ABC, Wall Street Journal, US News, and many others. He's been working on this line of immunotherapy research for many years.

I can't tell you how proud i am to be related to this guy. :)

I'm giving the musical tuning lecture again! Enough people missed it, and wanted to see it, that i decided to schedule a second run. Tomorrow night (Tuesday), Kingman Hall, 8:30pm in the fireplace room. Feel free to drop by.

The lecture went well! I had a good, engaged audience — a little over a dozen people, i think — and they put up with the multiple glitches in my presentation software. I wrote the software to do these animations using Pyglet, a multimedia library for Python.

Here's a condensed version of the first part of the lecture. It isn't quite the same without the audio — we could play the notes depicted on these slides, to hear the intervals we were talking about. But i'll try to explain the ideas in text.

* * *

Musical notes are oscillations, and the pitch of a musical note is determined by the frequency of the oscillation. (There are often many different frequencies embedded in the sound of a particular instrument, but the pitch we hear is usually the loudest and lowest of the frequencies.)

Two notes played together sound harmonious if their frequencies are in a ratio of small integers. That's because when the ratio is simple, the combination of waves makes a simple repeating pattern like the pair of waves on the bottom of this picture. The pair on top are not in a simple ratio, so the pattern doesn't repeat exactly.

The ratio between 300 Hz and 600 Hz is 1 to 2, the simplest possible ratio of two different notes. We hear that as an octave — such a basic interval that the two sound like the "same note". Here are the four octaves starting from 100 Hz — they go up to 200, 400, 800, and 1600 Hz. Plotted on a logarithmic scale, all ratios of 1 to 2 appear as equal distances. I'll mark this distance with a red bar.

Let's zoom in on one of these octaves and see what other ratios look like. I'll drop the "Hz" for now and mark the starting frequency just as 1. The next simplest ratio is from 2 to 3; i'll mark that with a blue bar. The ratio from 3 to 4 gets a green bar. And the ratio from 4 to 5 gets a yellow bar.

The ratio from 2 to 4 is also an octave. And the blue interval and green interval fit neatly inside — so they add up to exactly an octave. The blue interval is known as a "perfect fifth" and the green interval is called a "perfect fourth" — the reason for these names will become clear in a moment when we've put together the major scale.

If you go a perfect fifth up from 1, you get to 3/2, or 1.5. And if you go a perfect fourth up from 1, you get to 4/3 (about 1.333). These fit symmetrically between 1 and 2 — you can imagine a line right down the middle, and the two notes on one side are a mirror image of the two notes on the other.

The yellow interval — the ratio 5/4 — is called a "major third". If you go up this much from 1, you get to 1.25. And the three notes 1, 1.25, 1.5 make a nice-sounding chord — this is the major chord. Let's construct a major chord starting at each of the three notes shown above: starting from 1, from 1.333, and from 1.5. Each major chord is a yellow-blue pair in the picture below.

The top note of the chord starting at 1.5 overshoots the top of the octave — it goes to 2.25, which is the ratio 9/4. The equivalent note within the octave is exactly half of that, at 9/8. These seven notes we've identified form the major scale — if we label them in increasing order starting from C, these are (approximately) the white keys on a piano. So this explains why there are seven white keys in each octave on a piano.

You can see now why C–E is called a "third" — E is the third note counting from the left, and C–F is called a "fourth" — F is the fourth note, and C–G is called a "fifth" — G is the fifth note. The frequencies you see above are the "just intonation" for the major scale.

Notice that the spaces between the notes are uneven — E and F are closer together than the rest, and so are B and C at the top of the scale. In each of the five bigger gaps, there's space for another note. These are the black keys on a piano — that's why there are five black keys in each octave.

But piano keys are not tuned exactly like the notes in the picture above. That's because the spaces that look about the same are not exactly equal. For example, although D looks about halfway between C and E, it isn't. The ratio of D to C is 9/8 = 1.125, but the ratio of E to D is 10/9 or about 1.111. That means that if you tune your notes according to these ideal ratios, the scale will only sound right when you start on C. The other intervals will be off. For example, the fifth note starting from D is A. But the interval D–A is not a perfect fifth; it's 40/27, or about 1.48, which sounds really off.

To make it possible to play in any key, pianos (and most modern instruments) are tuned so that all twelve notes are equally spaced within the octave. This picture compares the justly-tuned major scale (on top) with 12 equal divisions of the octave (on the bottom).

By an amazing coincidence, when you divide the octave (a multiplicative factor of 2) into 12 equal parts (each a multiplicative factor of 2^1/12), you get notes that closely correspond to every note of the major scale. For example, 7 of these 12 parts almost exactly make a perfect fifth: 2^7/12 is very nearly equal to 1.5. Where the lines match up, you have a white key on the piano; and where there is a missing line on top, that's where you have a black key.

When you tune the piano to this system, which is called "12-tone equal temperament", the scale starting from any key sounds exactly the same. This means you can write music that shifts from key to key freely, without fear of ending up in a bad-sounding scale — all the scales sound equally good. The scales are a little off from what they should be, though. The fifth on an equal-tempered keyboard sounds pretty much indistinguishable from a real perfect fifth; but you see how the E doesn't quite match up? The major third is off by an amount that you can hear if you listen closely. The A is off by even more.

One of the big surprises for me when i learned about this stuff is that the 12-semitone system is rather arbitrary. It's not mathematically fundamental; it's a compromise: an approximation we invented. All of Western music is based on it, which, in a way, makes all of Western music a kludge. And it is impossible to tune the notes both in simple ratios and allowing modulation freely between all keys. The frequencies can never match up, because the just tunings are rational numbers, and any equal division of the octave will produce irrational numbers (nth roots of 2).

(I then wandered off into talking about the scales in other cultures, and we listened to samples of music from these other cultures and from modern experiments in 19-tone and 13-tone equal temperament.)

( All the visuals. )

I'm giving a lecture at Kingman tonight at 8 pm on musical tuning systems. Ever wondered:

• ...why there are 12 notes in an octave?
• ...why there are 7 notes in a major scale?
• ...why they have the pitches they have?
• ...what pitches the Ancient Greeks used?
• ...what notes make a scale in Arabic music?
• ...what music in a 13-note scale sounds like?

Consider this a sincere form of flattery, then.

Conversations These Days

(The backstory: a friend of mine complained to me about how her dad doesn't answer her questions anymore; when she asks him something, he just tells her to look it up on Wikipedia. The trueness of this comment as applied to life in general made me think, this is the perfect kind of thing for an xkcd... so i decided to draw one.)

If you have ever loved or cared for me, i would like to say thank you. I realized i wanted to say this a little while ago, when i was cleaning up my room and came across some of the letters and notes i've received from people who were close to me. They reminded me how incredibly lucky i've been.

You know who you are, and i'm grateful to you, even if we've fallen out of touch or out of favour with each other since then. Being cared for by you was and is a privilege. It has helped to make me the person i am. All i am is a collection of experiences shared and things learned from other people, and some of the best parts have come from you. Sometimes i forget this. I'm going to try harder to remember it, and to carry forward what you've given me in the way i live my life.

This is one of the funniest and most awesome things i have read in a long time. Definitely worth checking out, especially if you ever wonder about the nature of consciousness.

GENERAL FRED: Are you sure?

SCIENTIST: As sure as we can be in the total absence of evidence.

When i arrived at the Intercontinental Hotel i was pleasantly surprised to run into tongodeon, who was there with a plan of his own. He brought the Attorney General a nice present — a Casio F91W wristwatch, with a polite and gracious note.

Indeed, my question was too long — much too long. I shortened it by half to write it onto an index card, which i brought with me to hand over. Then i had to shorten it drastically again to re-write it onto the special Official Commonwealth Club Question-Asking Card that they provided. (Yes, i misspelled Miers' name.)



Mukasey spent his entire speaking time lecturing us on government corruption. The hypocrisy was really quite breathtaking: he went on at some length about being a nation of laws and not of men, about the importance of providing a check and balance on every part of government, about ensuring that public officials are accountable and corruption be vigourously pursued and fairly prosecuted wherever it is found, regardless of political party. It was all i could do to keep myself from interjecting, "Yes — so stop protecting the President and hold him to the rule of law like everyone else!"

At the end of the session, the moderator did finally ask my question, or something on the topic, anyway. But she didn't read what i wrote; she filtered and edited every question down for politeness. The closest she got to anything resembling criticism was to say there were some questions from the audience about his consistency with respect to corruption. All she asked him was to offer his comments on the subpoenas on Bolten and Miers. So he simply repeated his old explanation: that the President's advisors should be able to talk privately to the President without being held to account. It was never pointed out that the law gives them no such permission, that neither he nor the President is allowed to tweak laws to suit their taste, or that he is protecting the Justice Department itself by ordering the Justice Department not to do its job.

He sounded so sincere and passionate in his main talk that i began to wonder if he simply has a blind spot when it comes to this executive. Perhaps he really has no idea that his actions are direct contributors to a dangerous consolidation of corruptible power in the White House. He continued to defend immunity for the telecom companies, the executive privilege to evade subpoenas, and his refusal to act against waterboarding without even the slightest awareness that there was anything wrong with letting the President freely order people to break the law.

All in all, it was probably not worth the money i paid for the ticket. But it was nice to see tongodeon again. An audio recording of the event should eventually appear online.


P. S. The Secret Service was there in force — at least a dozen men in dark suits with the trademark coil of clear plastic cord running from the left ear to the shirt collar. I always thought it was a Hollywood thing, but no, they really do get that far-off look and touch their ears with their hands when someone is talking to them on the radio.

P. P. S. (Added.) Thanks to tongodeon for providing this link to the prepared text of Mukasey's speech. Choice quotations include:

• "We are, as we proclaim repeatedly, a nation of laws, not men."
  
• "The survival and prosperity of a government of laws depends in great measure on the integrity of the men and women who pass, enforce, and administer the laws by which we are governed."
  
• "When a public servant at any level of government exploits his or her office for improper purposes, the damage is measured not just in dollars and cents but also in erosion of the public trust – upon which depends the survival of our system of government."
  
• "The investigation and prosecution of public corruption is therefore among the highest obligations of law enforcement."

I found out that Attorney General Michael Mukasey is speaking at the Commonwealth Club tomorrow. I decided to buy a ticket and attend, figuring i might not get a chance like this again. I hope to ask him:

Title 2, Section 192 of the U. S. Code says that refusing to testify or produce documents in response to being summoned by Congress is a misdemeanor punishable by fine and imprisonment. It does not equivocate. It doesn't say it's a misdemeanor unless the President prefers someone not to testify. Section 194 says that when someone violates Section 192, a U. S. attorney has the duty to bring the matter before a grand jury. It doesn't say that this duty only exists unless the President prefers the law not to be enforced.

I refer, of course, to the violation by Mister Bolten and Miss Myers of Section 192, and the refusal by Mister Taylor to perform his duties under Section 194. Surely you are aware that there is no hope of upholding the rule of law if those who are duty-bound to enforce laws choose to enforce them selectively, at the whim of those against whom they would be enforced. Will you now commit to perform your duty as attorney general and uphold these laws, or will you explain to us, assembled here in this room, why you and Mister Taylor should not be prosecuted for obstruction of justice, and why anyone should believe that you are serious about eliminating corruption when it is your own department that is protected from scrutiny by your continuing failure to enforce the law?

I'm starting a new open source project. It's something i've been thinking about for quite a while now, and have mentioned to people here and there. Let me tell you a bit about it.

Exhibit A: a book on gender differences

Catching and recovering from misconceptions

An idea for a new service

• The site is a database of claims.
  
• Each claim has lists of supporting and refuting citations.
  
• Each citation quotes from a source and explains how it relates to the claim.
  
• Each claim can also have supporting and refuting arguments.

A modest start

Last week i went to the Python Conference in Chicago. It was good to be among that crowd of familiar faces again. I've been feeling somewhat anxious and lonely lately in anticipation of the shift from school to Real Work and my imminent move out of the co-ops (yes, that's still months away but it makes me sad), so it's nice to be reminded of a community i can continue to be a part of. Quite a few Python hackers are at Google (including Guido himself), so i may be seeing more of them soon.

As usual, the hallway sessions were the best. Some of the talks were pretty fun too, but the best part of it for me was just feeling like part of the flow and catching up with all the interesting things people are working on. It's nice to be somewhere where most people either know who you are or are excited to get to know you.

PyCon was huge this year — something like 1100 people, compared to 600 last year. It was estimated that, assuming the current geometric growth rate continues, the entire population of the planet would be attending PyCon in some small number of years.

This was the first time i stayed afterwards for the coding sprints. Sprinting is a simple concept: get in a room with a bunch of other programmers and code all day. Even though it sounds just like work, somehow it's a lot more fun. I think it's a combination of working directly with awesome people (e.g. having the creator of Python sitting just two chairs over, or a co-creator of Django sitting across the table, so you can ask questions when you get stuck) and the focus brought on by the limited time and the specificity of the tasks. The atmosphere is different when everyone has flown in to be at the sprint and you know you're only going to be there for a few days. Travelling also gives you an excuse to ignore some of the sources of distraction that exist at home and at the office.

I did a little work on Python 3.0. It felt good to be productive and efficient. I got in 12 hours of work in a day, felt fine, and got decent, regular sleep. (I was hoping to keep it up, but alas, my sleep schedule immediately disintegrated and productivity plummeted upon returning home.) I've been carrying some guilt because i've been a long-time member of the core Python development team, with commit privileges and all, and have contributed absolutely nothing for the past few years. I think i get consistently too much credit in the Python community, both because of that unearned status and because of a bug-tracking program called Roundup that is awesome but that i didn't write. (Once upon a time, i wrote a proposed design for a bug-tracking program — basically a wishlist of things i thought would be cool to have. Richard Jones then did all the hard work to actually build it, but people keep complimenting me on it just because the name was initially associated with me.) The work I did at the sprint (which had to do with the handling of Unicode in the new file I/O module, if you're curious) was pretty small, but at least it was something. I hope i continue to have time to contribute.

I did finally make a decision about what to do next with my life. I'm going to be joining Google.org in San Francisco. The work they're doing is very exciting — they're taking on some of the really big problems in our world, and i'm thrilled to be joining them. I think two of the biggest factors for me are (a) the huge learning opportunity of working with experts in international health and development, and (b) the openness of the "dot-org" side of the company. Google's culture of intense secrecy was one of the main concerns i had about working for them, and this seems to be much less of an issue at Google.org.

As i understand it, Google.org is not a separate non-profit organization. It's part of Google, and in many ways i will be just another Google engineer. But it does have a distinct mission, and compared to Google as a whole it is relatively young.

I owe my thanks to everyone who had comments and advice to offer as i was pondering this big decision. Having the support of so many wise friends helped a lot. I'm also grateful to many friends who are now at Google, for encouraging me to look into this possibility and for whatever good words they may have put in on my behalf to make this opportunity real.

I can't wait to start playing my small part in efforts to solve some of our biggest problems!

Here's my picture now:

I realize that everyone probably has different ideas about what should go on this picture, and what arrows should connect them. I think that's interesting — what you choose to put on the diagram says something about your worldview.

So: take a few minutes to draw your own diagram. Then take a picture of it and post it in a comment here, or post it on your blog/journal and leave a comment here.

I'm curious to see what will show up in everyone else's drawings.

I've been doing a little brainstorming. Here's what i have so far.

If there were no externalities, the free market would solve everything. But that's not real life. So this is a picture of influences that occur outside the free market.

(Updated Feb. 29, 7pm: added "war -> poverty" link and "religion" bubble.)

The completely connected triangle — education, health, and poverty — is interesting.

There are people, organizations, and movements sitting on each of these arrows trying to influence them. These are some of the "good guys":

• Scientific American, MythBusters, etc.
• Sam Harris, Richard Dawkins, etc.
• PLoS, open access movement
• campaign finance laws
• truth in advertising laws
• responsible bloggers
• Wikipedia
• FactCheck, NewsTrust, etc.
• Change Congress
• electoral system reform
• voting machine reliability
• OpenCongress, TheyWorkForYou
• Americans United

Where do you fit on this picture?

This is the entry in which i confess to one of my compulsive behaviours. My sleep cycle is not the most regular thing in the world (but then again, i hear this is not so unusual for hacker types). Once upon a time i got interested in my sleep patterns,¹ and decided to start recording them. So i hacked up a little utility to help me keep a log of when i sleep and wake up, with fairly minimal effort.

When i started writing my dissertation, it occurred to me that it would be nice to know how much time i spent on the thing when i was finally done with it. So i made a habit of recording when i worked on that too. Now i have hundreds of little timestamped log entries.

What does one do with all this data? Visualize it, of course...

Time spent on the dissertation (orange): 327.9 hours
Time spent on the talk (purple): 41.4 hours
Total: 369.3 hours

(Made with Python and ReportLab, then marked up with OmniGraffle.)

Note 1. I also tried living on a 28-hour day (with a 6-day week) for a few weeks one summer. It was interesting. But that is a story for another time.

So... i'm trying to organize my thoughts on what to do with my life. I've been out of school for a month, interviewing for jobs and coming up with project ideas. I decided that writing might help me sort this out, so i'm going to do some of my thinking here, in the open. I invite your reactions and opinions — some of you know me very well, and your feedback could help me out.

Desiderata

1. number of people who benefit
   
2. degree of impact of the project
   
3. degree of my personal impact on the project
   
4. likelihood of success
   
5. necessity of my participation

What is the most important problem?

Your opinions here...

• For me, enjoyment and motivation go hand in hand. If i realize that what i'm doing isn't that significant after all, the motivation will go away and i'll stop enjoying it. So part of the point of this exercise is to construct an argument strong enough for whatever choice i make, such that i can maintain conviction in my choice and continue to enjoy it, long enough to actually achieve something.
• Also, there's something that feels intellectually dishonest about choosing an answer just because i like it rather than because it's right. I'm hoping to find more solid grounding for my decision.

Larry Lessig explains the significance of tomorrow's primary.

I would go further; i think there are real policy differences between Obama and Clinton that matter, and that weigh decisively in favour of Obama (technology policy, for example). But i can't vote in this election, so i'll just share Lessig's video with you. Now is not the time to be afraid. Now is the time to reach for new hope.

There are so many more thoughtful and significant things i've been wanting to post about for a few weeks now. I hope i get to them. But today i couldn't resist posting a link for you:

Best comment EVAR.

zestyping ... you're an idiot. I rest my case.

Why?

How about this comparison ... you can stick it in any language you want even your asss...
try this piece of code on any compiler....

if ("zestyping" > "all idiots around the world") {
echo "It's true, on all compilers";
}
...wow...I'm amazed ... it returns true, they should stop you from touching the keyboard.
OMFG.

So by now everyone knows that Obama and Huckabee won the Iowa caucuses. But perhaps less well known is the dramatic difference in voter turnout — between Democratic and Republican, and in 2008 compared to previous years.

Iowa Caucus Turnout, 2000–2008
2000
60 760	87 666
2004
124 000	uncontested (George W. Bush)
2008
221 000	116 114

Some of the numbers above are approximate, but the trend is clear: a huge increase in Democratic caucus participants (78% more than in 2004, and 90% more Democrats than Republicans this year). My understanding is that the Democratic caucuses also require more time and involvement than the Republican ones. All of this adds up to a lot of enthusiastic Democrats — at least in Iowa.

Here's what that looks like if you break down each bar according to the proportion of support that each candidate received.

Iowa Caucus Vote Distribution, 2000–2008
2000
Bradl Gore	Bush Forbes Ke B
2004
Ge Dean Edwards Kerry	uncontested (George W. Bush)
2008
Clinton Edwards Obama	Huckabee Romney Tho Mc Pa

What do you think this means for the election as a whole? Is this phenomenon local to Iowa, or is it a sign of things to come?

Sources: MSNBC, AP, CNN, Eric Appleman.