Added: Prizewinners announced in this comment below.
This post is an announcement of a prize for the best exercises submitted in the next two weeks on a topic of your choice, that are of interest to the LW community. We're planning to distribute $1,000, where $500 of that will go to the first place.
To submit some exercises, leave a comment here linking to your exercises by midnight at the end of Friday 20th September PDT (San Francisco time). You can PM one of us with it if you want to, but we'll be publishing all the entries that win a prize.
I want to talk about why exercises are valuable, but my thinking is so downstream of reading the book Thinking Physics, that I'd rather just let its author (Lewis Carroll Epstein) speak instead. (All formatting is original.)
The best way to use this book is NOT to simply read it or study it, but to read a question and STOP. Even close the book. Even put it away and THINK about the question. Only after you have formed a reasoned opinion should you read the solution. Why torture yourself thinking? Why jog? Why do push-ups?
If you are given a hammer with which to drive nails at the age of three you may think to yourself, "OK, nice." But if you are given a hard rock with which to drive nails at the age of three, and at the age of four you are given a hammer, you think to yourself, "What a marvellous invention!" You see, you can't really appreciate the solution until you first appreciate the problem.
What are the problem of physics? How to calculate things? Yes - but much more. The most important problem in physics is perception, how to conjure mental images, how to separate the non-essentials from the essentials and get to the hear of a problem, HOW TO ASK YOURSELF QUESTION. Very often these questions have little to do with calculations and have simple yes or no answers: Does a heavy object dropped at the same time and from the same height as a light object strike the earth first? Does the observed speed of a moving object depend on the observer's speed? Does a particle exist or not? Does a fringe pattern exist or not? These qualitative questions are the most vital questions in physics.
You must guard against letting the quantitative superstructure of physics obscure its qualitative foundation. It has been said by more than one wise old physicist that you really understand a problem when you can intuitively guess the answer before you do the calculation. How can you do that? By developing your physical intuition. How can you do THAT? The same way you develop your physical body - by exercising it.
Let this book, then, be your guide to mental pushups. Think carefully about the questions and their answers before you read the answers offered by the author. You will find many answers don't turn out as you first expect. Does this mean you have no sense for physics? Not at all. Most questions were deliberately chosen to illustrate those aspects of physics which seem contrary to casual surmise. Revising ideas, even in the privacy of your own mind, is not painless work. But in doing so you will revisit some of the problems that haunted the minds of Archimedes, Galileo, Newton, Maxwell, and Einstein. The physic you cover here in hours took them centuries to master. Your hours of thinking will be a rewarding experience. Enjoy!
What does this look like?
Here are exercises we've had on LessWrong in the past.
- Scott Garrabrant and Sam Eisenstat's Fixed Points Exercises, which had dozens of commenters completing them and submitting their answers.
- Eliezer's Highly Advanced Epistemology 101 For Beginners has many meditations - while not exactly exercises, they were key problems that commenters gave answers to and then got to see Eliezer's answers in the subsequent post. Eliezer also previously challenged readers to not solve Free Will, but to dissolve it. It had several setup and follow-up posts that helped.
- John Wentworth has posted exercises in chemistry and deck-building to grapple with the concept of slackness.
- RobinZ made some exercises to test the reader's understanding of Making Beliefs Pay Rent in Anticipated Experience.
- Alkjash set a final exam in his hammertime sequence on rationality, inviting people to invent their own rationality technique, leading 7+ readers to write their own posts with their results.
- Eliezer created an exercise prize once before, $50 for any exercise that CFAR actually tested, and $500 for any suggestion that was turned into a CFAR class. They asked for exercises that taught people to Check Consequentialism, to Be Specific, and to Avoid Motivated Cognition. Winners who got the full $550 were Palladias's Monday/Tuesday Game and Stefie_K's Vague Consultant Game.
- CFAR has a rationality checklist on their website. It doesn't have correct answers, but it operationalises a lot of problems in a helpful way.
In my primer on Common Knowledge, I opened with three examples and asked what they had in common. Then, towards the end of the post, I explained my answer in detail. I could've trivially taken those examples out from the start, included all the theory, and then asked the reader to apply the theory to those three as exercises, before explaining my answers. There's a duality between examples and exercises, where they can often be turned into each other.
But this isn't the only or primary type of exercise, and you can see many other types of exercise in the previous section that don't fit this pattern.
What am I looking for in particular?
I'm interested in exercises that help teach any key idea that I can't already buy a great textbook for, although if your exercises are better than those in most textbooks, then I'm open to it too.
Let me add one operational constraint: it should be an exercise that more than 10% of LessWrong commenters can understand after reading up to one-to-three posts you've specified, or after having done your prior exercises. As a rule I'm generally not looking for a highly niche technical problems. (It's fine to require people to read a curated LW sequence.)
I asked Oli for his thought on what makes a good exercise, and he said this:
I think a good target is university problem sets, in particular for technical degrees. I've found that almost all of my learning in university came from grappling with the problem sets, and think that I would want many more problem sets I can work through in my study of both rationality and AI Alignment. I also had non-technical classes with excellent essay prompts that didn't have as clear "correct" answers, but that nevertheless helped me deeply understand one topic or another. Both technical problem sets and good essay prompts are valid submissions for this prize, though providing at least suggested solutions is generally encouraged (probably best posted behind spoiler tags).
(What are spoiler tags? Hover over this:)
This is a spoiler tag! To add this to your post, see the instructions in the FAQ that's accessible from the frontpage on the left-menu.
(Also see this comment section for examples of lots of people using it to cover their solutions to exercises.)
Give me examples of things you think could have exercises?
I think exercises for any curated post or curated sequence on LessWrong is a fine thing. I've taken a look through our curated posts, here are a few I think could really benefit from great exercises (though tractability varies a lot).
- Mistakes with Conservation of Expected Evidence
- Why Subagents?
- Coherent decisions imply consistent utilities
- Asymmetric Justice
- Thoughts on human models
- Disentangling arguments for the importance of AI Safety
- Less Competition, More Meritocracy
- Meditations on Momentum
- Norms of Membership for Voluntary Groups
- Embedded Agency
- Coordination Problems in Evolution: Eigen's Paradox
- The Rocket Alignment Problem
- Unrolling social metacognition: Three levels of meta are not enough
- Prediction Markets: When Do They Work?
- Beyond Astronomical Waste
- Meta-Honesty: Firming Up Honesty Around Its Edge-Cases
- Decision theory and zero-sum game theory, NP and PSPACE
- Tech economics pattern: "Commoditize Your Complement"
- On exact mathematical formulae
- Local Validity as a Key to Sanity and Civilization
- A voting theory primer for rationalists
- A Sketch of Good Communication
- The Costly Coordination Mechanism of Common Knowledge
- Argument, intuition, and recursion.
I think technical alignment exercises will be especially hard to do well, because many people don't understand much of the work being done in alignment, and the parts that are easy to make exercises for often aren't very valuable or central.
Some of Nick Bostrom's ideas would be cool, like the unilateralist's curse, or the vulnerable world hypothesis, or the Hail Mary approach to the Value Specification Problem.
Feel free to leave a public comment with what sort of thing you might want to try making exercises for, and I will reply with my best guess on whether it can be a good fit for this prize.