DuncanS

Karma: 594

DuncanS May 18, 2012, 9:00 PM
3 points
on: Be careful with thought experiments
It depends on your thought experiment—mathematics can be categorised as a form of thought experimentation, and it’s generally helpful.

Thought experiments show you the consequences of your starting axioms. If your axioms are vague, or slightly wrong in some way, you can end up with completely ridiculous conclusions. If you are in a position to recognise that the result is ridiculous, this can help. It can help you to understand what your ideas mean.

On the other hand, it sometimes still isn’t that helpful. For example, one might argue that an object can’t move whilst being in the place where it is. And an object can’t move whilst being in a place where it is not. Therefore an object can’t move at all. I can see the conclusion’s a little suspect, but working out why isn’t quite as easy. (The answer is infinitesimals / derivatives, we now know). But if the silly conclusion wasn’t about a subject where I could readily observe the actual behaviour, I might well accept the conclusion mistakenly.

Logic can distill all the error in a subtle mistake in your assumptions into a completely outrageous error at the end. Sometimes that property can be helpful, sometimes not.

DuncanS May 10, 2012, 9:32 PM
1 point
in reply to: jdinkum’s comment on: [Error communicating with LW2 server]
Here’s what I tend to do.

On my first draft of something significant, I don’t even worry about style—I concentrate on getting my actual content down on paper in some kind of sensible form. I don’t worry about the style because I have more than enough problems getting the content right.

In this first draft, I think about structure. What ONE thing am I trying to say? What are the 2-5 sub-points of that one thing? Do these sub-points have any sub-points? Make a tree structure, and if you can’t identify the trunk, go away until you can.

Then I go back and fix it. Because the content is now in roughly the right place, the second run-through is much easier. But normally that helpful first draft is full of areas where the logical flow can be improved, and the English can be tightened up. I think you’re missing this stage out entirely as when looking at your post I can find plenty to do. Here’s what five minutes of such attention does to your first para.

“When I was 12 I started an email correspondence with a cousin, and we joked and talked about the things going on in our lives. This went on for years. One day, several years in, I read through the archives. It saturated my mind with the details of my life back then. I had the surreal feeling of having traveled back in time—almost becoming again the person I was years ago, with all my old feelings, hopes and concerns.”

Keep at it—there’s plenty enough there for the polishing to be worthwhile.

DuncanS May 3, 2012, 3:46 PM
22 points
on: Punctuality—Arriving on Time and Math
As a purely practical measure, for really important occasions, I’ll often plan in an activity at second-to-last which is actually unimportant and can be dropped. So, for example, if I have a job interview, my plan will be that, after I’ve found the entrance to the company office and there is as little left to go wrong as possible, I’ll then, as a second-to-last activity, do something like go for a relaxed lunch at a nearby cafe, and then just stroll in at the ideal time.

On the day everything goes to pot, I can use up the time I planned for the second-to-last activity. So I should hopefully still have time to go back for the forgotten briefcase, hire a taxi from my broken-down car, replace my torn shirt, and still get to the interview hungry rather than two hours late.

This is a good plan for anything with a hard start time—weddings, theatre trips, plane trips—add a pleasant activity that you can delete if needed at second-to-last. Of course the length of this optional activity should be at least as long as the number of sigmas you need for the important one. The result is that you arrive on-time and de-stressed (almost) every time.
What links here?
- JenniferRM's comment on Punctuality—Arriving on Time and Math by Xachariah (May 3, 2012, 10:42 PM; 3 points)

DuncanS Apr 30, 2012, 10:06 PM
0 points
on: (Almost) every moral theory can be represented by a utility function
One thing that goes along with this is the idea that possible courses of action in any given situation can be sorted according to moral desirability. Of course in practice people differ about the exact ordering. But I’ve never heard anyone claim that in the moral sphere, B > A, C > B and simultaneously A > C. If in a moral scheme, you always find that A > B > C implies A > C, then you ought to be able to map to a utility function.

The only thing I’d add is that this doesn’t map onto a materialist consequentialism. If you were part of the crew of a spacecraft unavoidably crashing into the Sun, with no power left and no communications—is there still a moral way to behave—when nothing you do will show in the material world in an hour or so? Many moral theories would hold so, but there isn’t a material consequence as such...

DuncanS Apr 29, 2012, 12:05 AM
4 points
on: [LINK] System 2 thinking decreases religious belief
This seems very similar to the experiment where black people were shown to do worse on intelligence tests after being reminded that they were black..

So this experiment (in my view) doesn’t really help to answer whether analytical thinking reduces religious belief. What it does show is that a lot of people make that association, and that is more than enough to cause the priming effect.

DuncanS Apr 21, 2012, 10:39 PM
0 points
in reply to: MarkusRamikin’s comment on: Stupid Questions Open Thread Round 2
It’s the process of changing your mind about something when new evidence on something comes your way.

The different jargon acts as a reminder that the process ought not be an arbitrary one, but (well, in an ideal world anyway) should follow the evidence in a way defined by Bayes theorem.

I don’t think there’s any particular definition of what constitutes, belief, opinion and cognitive structure. It’s all just beliefs, although some of it might then be practised habit.

DuncanS Apr 17, 2012, 8:46 PM
16 points
on: Question about brains and big numbers
I think there are some confusions here about the mind’s eye, and the way the visual cortex works.

First of all, I suggest you do the selective attention test. Here will do. Selective attention test

This video illustrates the difference between looking at a scene and actually seeing it. Do pay attention closely or you might miss something important!

The bottom line is that when you look at the outside world, thinking that you see it, your brain is converting the external world of light images into an internal coding of that image. It cheats, royally, when it tells you that you’re seeing the world as it is. You’re perceiving a coded version of it, and that code is actually optimised for usefulness and the ability to respond quickly. It’s not optimised for completeness—it’s more about enabling you to pay attention to one main thing, and ignore everything else in your visual field that doesn’t currently matter.

And that’s where your comparisons later fall down. The computers rendering Avatar have to create images of the fictional world. Your own internal mind’s eye doesn’t have to do that—it only has to generate codes that stand for visual scenes. Where Avatar’s computers had to render the dragon pixel by pixel, your internal eye only has to create a suitable symbol standing for “Dragon in visual field, dead centre.” It doesn’t bother to create nearly all of the rest of your imagined world in the same way as some people ignore the important thing in the attention test. Because you only EVER see the coded versions of the world, the two look the same to you. But it is a much cheaper operation as it’s working on small groups of codes, not millions of pixels.

The human brain is a very nice machine—but I also suspect it’s not as fast as many people think it is. Time will tell.

DuncanS Apr 15, 2012, 10:07 PM
8 points
on: More intuitive programming languages
I am a programmer, and have been for about 20 years or so. My impressions here...

Diagrams and visual models of programs have typically been disappointing. Diagrams based on basic examples always look neat, tidy, intuitive and useful. When scaling up to a real example, the diagram often looks like the inside of a box of wires—lines going in all directions. Where the simple diagram showed simple lines drawing boxes together, the complex one has the same problem as the wiring box—you have 40 different ‘ends’ of the lines, and it’s a tedious job to pair them all up and figure out what goes where.

Text actually ends up winning when you scale up to real problems. I tend to find diagrams useful for describing various subsets of the problem at hand, but for describing algorithms, particularly, text wins.

The problem of programming is always that you need to model the state of the computer in your head, at various levels. You need to be able to ‘run’ parts of the program in your head to see what’s going on and correct it. This is the essential aspect of programming as it currently is, and it’s no use hoping some language will take this job away—it won’t, and can’t. The most a language can do is communicate the algorithm to you in an organised way. The job you mentioned—of modelling the flow of instructions in your head, and figuring out the interactions of distant pieces of code—that is the job of the programmer, and different presentation of the data won’t take that job away—not until the day AI takes the whole job away. Good presentation can make the job easier—but until you understand the flow of the code and the relationships between the parts, you won’t be able to solve programming problems.

On the other hand—I feel that the state of computer programming today is still almost primitivist. Almost any program today will show you several different views of the data structure you’re working on, to enable you to adjust it. The exception, by and large, is writing computer programs—particularly within a single function. There you’re stuck with the single view in which you both read and write. I’m sure there is something more that can be done in this area.

DuncanS Apr 7, 2012, 5:16 PM
1 point
on: Looking for reductionism help
I think one ought to think about reductionism slightly separately from the particulars of the universe we actually live in. I think of it as rather like the opposite of a curiosity-stopper—instead of assuming that everything is ontologically basic and doesn’t have underlying parts, we should assume that there may be underlying parts, and go look for them. Of course in our own universe that approach has been exceptionally fruitful.

The other part that works well is Occam’s razor—the simplest explanation of any data set is not only the most lightweight way of explaining the facts, it’s also the optimum way of expressing your state of ignorance as well. The simplest explanation is also the most compact way of explaining what you do know. That again arises purely out of the nature of information, and would be true in any universe, not just the noticeably elegant one we actually live in.

On the other hand, there may well be a final set of underlying parts that experiment actually points to, and there’s nothing wrong with that as long as it covers your experimental data.

DuncanS Apr 3, 2012, 11:36 PM
3 points
in reply to: Manfred’s comment on: John Danaher on ‘The Superintelligent Will’
The problem is that the utility isn’t constant. If you, today are indifferent to what happens on future Tuesdays, then you will also think it’s a bad thing that your future self cares what happens on that Tuesday. You will therefore replace your current self with a different self that is indifferent to all future Tuesdays, including the ones that it’s in, thus preserving the goal that you have today.

DuncanS Apr 3, 2012, 9:18 PM
2 points
in reply to: XiXiDu’s comment on: Evidence for the orthogonality thesis
To act maximally intelligently and correctly could quite easily be an instruction to convert the observable universe into a computer.

DuncanS Apr 2, 2012, 10:45 PM
10 points
on: Fictional Bias
Shame it’s a fictional study, as the effect is almost certainly absolutely real and measurable. Study after study suggests that any association that pops up in your mind affects your behavior—I see no reason why fictional associations would be any less effective than all the other logically inapplicable associations which have been shown to have this kind of an effect. Here’s an essentially randomly picked study on such things—it was just the first one I found googling for this kind of effect. The stereotype effect

DuncanS Mar 26, 2012, 11:10 PM
2 points
in reply to: handoflixue’s comment on: How to avoid dying in a car crash
There you might be a little different—I’m always either looking in or out—there isn’t any fusion between the two. Although I have to say I’ve never tried pushing a fictional thing into the external view—if I try it now I find myself looking at an internal view of what I’ve just been looking at externally, which is not the same thing. Perhaps in your case the barrier can be persuaded to be less absolute.

One thing that’s interesting about the two fingers test is that it can be easy to persuade yourself that you can pass it, but a friend will quickly tell you the truth. When you switch to internal imagery, you don’t just lose awareness of the visual scene, you also lose awareness of the fact that your visual finger switching missed a beat. It’s easier for someone else to see it.

DuncanS Mar 26, 2012, 9:55 PM
4 points
in reply to: handoflixue’s comment on: How to avoid dying in a car crash
Your brain gives the illusion that you can, because it can switch quite quickly. But this is just like the illusion that you can see the whole world around you—it’s not actually so. The proof is straightforward, and needs a friend.

One person holds up two fingers, one on each hand, and holds them up about a foot apart in front of them. The other person looks rapidly back and forth between the two fingers, switching their gaze from finger to finger twice a second in a regular rhythm. It’s not that hard to do this.

The person holding up the fingers watches the eyes of the other person, and once they’ve established a rhythm they ask them a visual memory question. They will be unable to answer it without breaking rhythm on their eye movements, which the friend can observe.

Corollary—you at some level only have one internal screen which can either view external images, or internal ones. Not both at the same time.

DuncanS Mar 19, 2012, 12:41 AM
27 points
on: How to avoid dying in a car crash
Here’s a few general principles I use.
- Notice near misses and any aggressive manoevres you have to make. Any violent manoevre that you have to make is quite possibly an accident if anything additional goes wrong. Ask yourself what caused them, and if there was anything you could have done differently to make the incident less dangerous. This includes cases where the other driver is principally to blame ! Basically, treat near misses like aircraft do—think of it as an accident that you luckily didn’t have, and try to find some way to avoid depending on luck next time.
- Don’t do things that nobody else will expect you to do. Doing something that nobody else is doing is dumb, not just because there might be a good reason not to do it, but also because nobody else will expect you to do it, and they may not allow for it. Follow the crowd unless you really know you’re out there by yourself. This obviously includes driving faster than everyone else, or stopping suddenly (if you don’t absolutely have to) etc.
- Never let your car go where your brain and observation haven’t been first. Drive to a complexity level that you can handle—if too much is going on, slow down until you can cope again. In my own driving, I guess I travel at the posted limit about 50% of the time—and when I’m going slower than that, it’s normally because of the needs of brain and observation. If you don’t have time to think about what you’re doing, you’re going too fast.
Similarly, schedule distracting things into time slots where not much else is happening on the road. Aggressively ignore any distraction that will take you over your complexity threshold. Stay off the phone as phone callers won’t allow for your driving situation—and avoid visual imagery as you literally can’t see while you’re imagining something visual.
- Give some (not too much) thought to how you’d feel about flattening some child who runs out in front of you. Maybe it was mostly their fault—but you are going to wonder what you could have done differently, and if you were really driving in a way that kept the risks reasonable. In residential areas, car parks and so on, react to the chance of a child you can’t see.
What links here?
- How to avoid dying in a car crash by [deleted] (17 Mar 2012 19:44 UTC; 125 points)

DuncanS 14 Mar 2012 23:09 UTC
14 points
0
on: How would you take over Rome?
I think we tend to underestimate the extent to which technologies arise out of the times they are found in—in many cases they arise almost as soon as they are practically possible. In many cases I suspect they arise before they are practically possible, and fail, repeatedly, until surrounding technology advances to the point that it’s possible to make them work. Steam engines, for example, weren’t invented until the 1700′s because metals were so bad at the time that pressure vessels were impossible to make safe—early cannon were extremely hazardous for this reason, and operated at low pressures. Early steam engines also couldn’t afford large amounts of metal, and were largely made of wood—a highly unsuitable material, and tended to use vacuum rather than pressure to work, as this kept the cylinders in compression, which was safer. They were consequently immensely inefficient, making a horse much more practical unless you happen to have lots of coal lying around.

Without any of the modern suppliers that we are all used to, it will be surprisingly hard to do much better than the Romans themselves did.

DuncanS 12 Mar 2012 21:49 UTC
−10 points
on: Slowing Moore’s Law: Why You Might Want To and How You Would Do It
Moore’s law is really hard to stop. Destroying all humans seems to be the only practical method of stopping it for any length of time, and even then I don’t think it would be permanent.

DuncanS 11 Mar 2012 16:44 UTC
9 points
on: On the etiology of religious belief
Anyone who knows toddlers knows this is a GAME.

Experimenter: “That’s a bear.” Toddler “Nooo it isn’t, it’s a bottle!” (Laughter)

You can bet the experimenter gave the whole thing away with lots of play-face expressions as well. The toddler probably trusts both speakers, but are expecting one of them to carry on fooling around.

DuncanS 11 Mar 2012 16:36 UTC
0 points
on: [Link, 2011] Team may be chosen to receive $1.4 billion to simulate human brain
Excised.

DuncanS 6 Mar 2012 21:38 UTC
5 points
on: Emotional regulation, Part I: a problem summary
One thing that helped me with this from an intellectual point of view was realising that this problem centers around an unprovable proposition. The proposition? That I am not a moron.

The problem’s straightforward. Suppose I come up with an argument that purports to show that I’m not such a moron after all. Who’s going to evaluate whether the argument is valid or not? Well, if it’s not me, the moron—the idiot who doesn’t know how to get stuff right. What am I doing trusting him?

Suppose instead someone else comes along and reassures me that I’m not a moron. Well, that’s nice, but someone has to validate whether or not they mean what they say, or whether they have good reason to be right about that or not. Who’s going to do that? You’re right—it’s me, the moron who has no idea.

So logically I can reach no answer regardless of whether I come up with a reason, or someone else does. Hey, if I’m a moron, I’m going to be wrong about this, aren’t I?

Nowadays, when I see the moron argument, I recognise it and say to myself—yes, yes—the moron argument. I know I can’t logically solve that—it’s insoluble. And I stop trying to think about it.

This of course doesn’t mean that I don’t sometimes do things that make me want the floor to swallow me up. Everybody does those things, and learning something when it happens is wise. But falling into the moron argument afterwards is—unhelpful—a known waste of CPU cycles better spent elsewhere.

There is an analogous situation that occurs with social status—perhaps I could call it the ‘loser’ argument. The same problem applies—once you wonder if you’re too much of a loser to know how much of a loser you are, you have a logically impossible problem to solve, and the only way to win that argument is to acknowledge that logic is powerless against it, smile and walk away.