If we care about preserving a "self" and we also believe that someone is still the same person when on drugs or when their hormones are playing up (this is not intended to be sexist, although I suppose it could sound like that) or when they are just really angry, then we shouldn't be too worries about brain chemistry.

There are new possibilities here for personal growth in ways that have not been possible before.

I agree. For a very positive spin on transhumanist brain chemistry engineering, I recommend reading http://biopsychiatry.com/

I guess most people who talk about "class" don't actually have a good idea about what it means. We have the approximate idea of "if you have more money and more power, you are a higher class", but most people are completely uncalibrated; they do not know how the power ladder actually works. So, as would be expected of humans, they usually divide the whole society into two classes, US and THEM, where "us" means people who make as much money as me, or less; and "them" means people who make more money than me. So the guy next door who makes twice as much money as I do is put into the same set as the oligarchs who rule the country. Then the oligarchs will make a law that increases the tax for the guy next door, and I will celebrate it.

(For example, the government of Slovakia created a new extra tax for "people with income between 2000 and 3000 euro monthly, except for lawyers" and called it "the millionaire tax". It was depressing to see all the left-wing people celebrating it, because if it is called "the millionaire tax" in the pro-government media, then of course it targets the millionaires, and not just some IT guy next doors. One could naively think that being ruled by Marxists for almost a century should give these people at least some insight into the class fight. But they merely remember the passwords.)

So far the best description of class system I found online is "The 3-ladder system of social class in the U.S." (I guess it pretty much works for other countries, too).

In my opinion, the critical part is to realize that class isn't money, although it correlates. Imagining that people with a lot of money are automatically upper-class, that is confusing the cause and the effect. The real causation is in the opposite direction. The upper-class people have sources of money unavailabble to muggles, but sometimes also an incredibly smart, intelligent and hard-working muggle can accumulate comparable amounts of money using completely different strategies. More articles from the same author:

Rich people are not automatically upper class. Steve Jobs was a billionaire but never entered it; he remained middle-class (in social position, not wealth) his entire life. His children, if they want to enter its lower tier, have a shot. Bill Gates is lower-upper class at best, and has worked very hard to get there. Money alone won’t buy it, and entrepreneurship is (by the standards of the upper class) the least respectable way to acquire wealth. Upper class is about social connections, not wealth or income.

The wealth of the upper class follows from social connection, and not the other way around. Americans frequently make the mistake of believing (especially when misled on issues related to taxation and social justice) that members of the upper class who earn seven- and eight-digit salaries are scaled-up versions of the $400,000-per-year, upper-middle-class neurosurgeon who has been working intensely since age 4. That’s not the case. The hard-working neurosurgeon and the well-connected parasite are diametric opposites, in fact. They have nothing in common and could not stand to be in the same room together, because their values are too much at odds.

Consider two analysts at a prestigious financial firm, both 24 years old and of equal drive, intelligence, and talent. Let’s also assume, for now, that none of their co-workers or managers know either analyst’s family background, except through their behavior. The middle-class kid spends the bulk of his time trying not to offend, not to behave in a way that might jeopardize the job he worked so hard to get and could not easily replace if he lost it. He doesn’t invite himself to meetings, avoids contact with high-ranking executives, and doesn’t offer suggestions when in meetings. Thanks to the fear he experiences on a daily basis, he’s seen as “socially awkward” and “mousy” by higher-ups. ... Even when they are cognitively aware of how to manage authority, the stakes of the career game for a middle-class striver, who will fall into humiliation and possibly poverty if he fails it, are so severe that only the well-trained and steel-nerved few can prevent these calamitously high risks from, at least to some degree, disrupting their game.

The rich kid, on the other hand, relates even to the highest-ranking executives as equals, because he knows that they are his social equals. He’ll answer to them, but with an understanding that his subordination is limited and offered in exchange for mentoring and protection. He views them as partners and colleagues, not judges or potential adversaries. Perhaps this is counterintuitive, but most of his bosses like this. His career advances fast. He respects others and himself and has an uncanny air of effortless “coolness” (by which I mean freedom from anxiety) that enables him to actually get things done. It becomes common knowledge that he’s “up-and-coming”, a rising star in his company. Even if his performance is smack-average or somewhat below, his effortless rise will not be deterred.

This “middle path” between self-defeat and entitled arrogance is narrow– a tightrope, metaphorically speaking. It is, I should note, of equal width and tension for both rich and poor. There is no intentional preference given to one class over the other. The difference is that children of wealth traverse it at a height of one meter over a mattress, while the middle-class and poor traverse it at a height of 20 meters over a lava pit.

I think I might have an advantage of being born in a Communist country, where the class differences not only existed just as strongly as they exist today (despite of what our propaganda was saying back then), but they existed in their raw form -- the power of social connections translated directly into the ability to help or hurt people, unobscured by the red herrings of education, skills and salary. (Education and skills are important to make this world a better place, but the social class is a different topic.)

There's two problems here. First, we have duplication of labor in that we have something like 1% of the population doing essentially the same task, even though it's fairly straightforward to reproduce and distribute en masse after it's been done once. This encompasses things like lesson plans, lectures, and producing supplementary materials (e.g. a sheet of practice problems).

This leads into the second problem, which is a resulting quality issue: if you have a large population of diverse talent doing the same task, you expect it to form some sort of a bell curve. As noted above, we can take any lecture, tape it, and broadcast in en masse fairly easily. When we choose a system where each student is subjected to their instructor's particular lecture, a relatively small portion of them get an excellent lecture, a very large portion get an average lecture (rather than an excellent lecture), and a relatively small portion get an execrable lecture (rather than an excellent lecture). If you're really ambitious, you could even get the top, say, ten lecturers together and have them collaborate to make a super-lecture, and then get feedback on that particular unit, so they can improve the superlecture into a super-duperlecture.

(IMO, this is still a suboptimal way to do things. Try that process on textbooks (which are much easier to write collaboratively), and instead of getting feedback on hour-long chunks, get feedback on section-sized chunks (which, depending on the subject, can something like one-tenth the size). A good textbook is also cheaper to write, cheaper to distribute, more updateable, and better didactic material to begin with.)

It's worth noting that there's still a few wrinkles. Most importantly, there's really no such thing as a "best" lecture, lesson plan, problem set, or textbook; the "goodness" quality depends, not just on the lecture's content, but the intended audience. Think of this as a callibration issue. For instance:

Last I checked, MIT uses Sadava as their introductory biology textbook. If you dig around the reviews, you will find endorsements of another introductory biology book by Campbell that claim it's "SO much easier to understand. It's better organized, more clearly written". When I found myself needing to relearn introductory biology (this time with Anki so I actually retain the knowledge), I tried Campbell, since that's what my high school used, but gave up not halfway through the first chapter, frustrated by the difficulty I had understanding, the poor organization, and unclear writing; I find Sadava, however, to be much easier to understand, better organized, and more clearly written. Is the quoted reviewer lying, perhaps paid off by Big Textbooks? Perhaps, but a much better explanation is that Sadava is more technical; it's much closer to the "definition-theorem-proof" feel of a math text. This makes it a fantastic text if you're most students at MIT (or a typical LWer), but much less so if you're in the other 99% of the population. This also solves the callibration problem: write two (or more) supertextbooks.

(This also neatly explains why MIT sometimse seems like the only school that uses good textbooks and why SICP only has 3.5 stars on Amazon.)

A second wrinkle is individual attention, which I tend to be dismissive of (if the textbook is good enough, you shouldn't need any individual attention! And it's not like the current education system, with its one-way lectures, is very good at giving very much individual attention), but if we're optimizing education, there probably is more individual attention given to every student. However, because of reasons, I suspect that most of it should come from students in the same class, not staff. Also, it belongs after the reading.

A third wrinkle is a narrowing of perspectives. In any particular domain, there's usually several approaches to solving problems, often coming from different ways of looking at it. In the current system, if you wind up on a team and come across a seemingly intractable problem, there's a good chance that someone else has happened across a nonstandard approach that makes the problem very easy. If we standardize everything, we lose this. This is somewhat mitigated by the solution to the callibration problem, wherein people are going to be reading different texts with the different approaches because they're different people, but we still kind of expect most mathematicians to learn their analysis from super!Rudin, meaning that they all lack some trick that Pugh mentions. The best solution I have is to have students learn in the highly standardized manner first, and once they have a firm grasp on that, expose them to nonstandard methods (according to my Memory text, this is an effective manner for increasing tranfer-of-learning).

What are some good examples of rationality as "systematized winning"? E.g. a personal example of someone who practices rationality systematically for a long time, and there are good reasons to think doing that has substantially improved their life.

It's easy to name a lot of famous examples where irrationally has caused harm. I'm looking for the opposite. Ideally, some stories that could interest intelligent, but practically minded people who have no previous exposure to the LW memeplex.

Is anyone aware of the explanation behind why technetium is radioactive while molybdenum and ruthenium, the two elements astride it in the periodic table are perfectly normal? Searching on google on why certain elements are radioactive are giving results which are descriptive, as in X is radioactive, Y is radioactive, Z is what happens when radioactive decay occurs, etc. None seem to go into the theories which have been proposed to explain why something is radioactive.

The prior distribution over hypotheses is distribution over programs, which are bit strings, which are integers. The distribution must be normalizable (its sum over all hypotheses must be 1). All distributions on the integers go to 0 for large integers, which corresponds to having lower probability for longer / more complex programs. Thus, all prior distributions over hypotheses have a complexity penalty.

You could conceivably use a criterion like "pick the simplest program that is longer than 100 bits" or "pick the simplest program that starts with 101101", or things like that, but I don't think you can get rid of the complexity penalty altogether.

Solomonoff induction justifies this : optimal induction uses a prior which weights hypotheses by their simplicity.

From what I understand, there is a debate in epistemology / philosophy of science regarding the concept of simplicity ("Occam's Razor"). Some hold that there is a justifiable basis for the concept in the sense that it is an indicator of which of a set of possible theories is more likely to be true. Others dispute this and say that there is no justified basis for simplicity arguments in this sense.

In a recent conversation I made the following assertion (more or less):

Those who say that simplicity arguments are unjustified are actually saying that we can never really know the truth about any theory at all, since there are always an infinite number of alternative and more complex theories that account equally for the data. The best we can do is to falsify a theory (as Karl Popper proposed), but beyond that we can never say anything about whether a theory is true.

So (I said), we have only one of two choices. We can either allow for simplicity arguments, or we can give up on ever saying anything positive about the truth (beyond falsifying a few of the infinite possible theories).

Is this correct?

Adding to Vulture's reply (that you can not make absolute positive statements about truth), the modern view of "Occam's razor" (at least in Bayesian thought) is the minimum description length (MDL) principle (http://en.wikipedia.org/wiki/Minimum_description_length), which can be rigorously formalized. In this formalism, it becomes a prior over models. Multiplied with the likelihood over models (derived from data), this gives you a posterior. In this posterior, if you have two models that make exactly the same predictions, the simpler one is preferred (note that the more complicated one isn't completely rejected; it's just given lower posterior probability).

There are very deep fundamental theoretical considerations for why MDL is a very good way of assigning a prior to beliefs. If someone wants to reject Occam's razor, they would have to give an alternative system and show that under the assumptions of MDL it gives better long-term utility. Or that the assumptions of MDL are unfounded.