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Comment Re:Is that why they lack perspective? (Score 3, Interesting) 205

Medieval art is not "poor quality" in my observation. It's often quite carefully done and ornate. Thus your theory about "done too well being idolatry" (paraphrased) does not hold much water in my opinion.

But that art it also highly abstract. The lack of perspective seemed to provide a symbolic feel to the images as if they are intended as icons or pictograms rather than literal images.

It may be they did that to make it easier to convey a story or social rankings to the uneducated masses. If you want to show a sequence or social rankings, for example, then perspective tends to get in the way because it would hide or "distort" the importance or order of things because it's affected by physical location rather than symbolic "location" in rank or time.

Look at a typical Windows desktop: the icons are rather flat and/or half-hazard in their perspective because they are not intended to mirror reality as their primary goal. (Well, okay, MS does lack art talent also :-)

Similarly, Sunday paper cartoons tend to down-play perspective because they are tuned to show a story, not a physical scene. Parts that help tell a story, such as faces, eyes, mouths, and hands are often bigger than normal relative to the rest of the body.

But, I do agree with your general premise that the purpose of art changes over time or per culture and it heavily affects the style.

It's also interesting that after camera technology become wide-spread, then the art of the day resorted to being more symbolic (cubism, impressionism, etc.). This is because cameras made realism a cheap commodity such that (well-done) symbolism was the new status symbol and difference maker.

Book Reviews

Submission + - The Outer Limits of Reason: What Science, Mathematics, and Logic Cannot Tell Us (mit.edu)

jenniefriedman27 writes: I was intrigued by a book advertisement I saw on the Boston MBTA: "An Exploration of The Scientific Limits of Knowledge That Challenges Our Deep-Seated Beliefs About Our Universe, Our Rationality, and Ourselves." At first I was a bit skeptical with such a bombastic line. But how can one resist such a come on?

This is a popular science book about what is beyond the ability of reason to know. By "reason" Yanofsky means anything using exact thought like math, logic, computers, physics and even a little philosophy. Questions of what human beings can know is part of a branch of philosophy called epistemology. Such philosophers usually talk about the theories of Lock, Berkley, Hume, Kant etc. In this book, the field is updated and scientific epistemology is discussed. There are many modern results that show that there are objects, that cannot exist, calculations that cannot be performed, and problems that cannot be solved. The book weaves a beautiful tapestry together and shows that many of these limitations in different fields are of the same form.

As a computer professional, I was naturally most interested in the two chapters about limitations of computers. Chapter 5 is about problems that can theoretically be solved but in fact, for any reasonable sized inputs will not be solved for trillions of centuries. The core of the chapter is the idea of NP-Complete problems such as Satisfiability (SAT) or the Traveling Salesperson Problem (TSP). One usually thinks of TSP as a hard computer problem that you can explain to any child, but Yanofsky stresses TSP as a limitation of human knowledge. He explains why most people believe there does not exist a simple algorithms for such problems. Yanofsky finishes this chapter off with a discussion of approximation algorithms and problems that are even harder than NP-Complete problems.

Chapter 6 is not about hard computer problems (complexity theory) but impossible computer problems (computability theory). The classic example is Turing's Halting Problem. There does not exist a program that can tell for any given program and any given input if the program with that input will halt or go into an infinite loop. The chapter also discusses some other unsolvable computer problem and shows how they are connected. There is a discussion of Turing's oracle idea and how this classifies all unsolvable problems. The chapters ends with a short (too short) and inconclusive discussion of whether humans — as opposed to computers — can solve such problems (is AI possible?)

The rest of the book deal with other types of limitations. Chapter 2 discusses limitations of language. Chapter 3 mentions some classical philosophical issues like Zeno's paradoxes and the topic of vagueness. Chapter 4 discusses the counterintuitive notions of infinity and the fact that there are different levels of infinity. Chapter 7 is about three fields of physics: chaos theory, quantum theory, and relativity theory. Chapter 8 deals with philosophy of science issues. Chapter 9 talks about some limitations of mathematics including some basic math problems that a computer (and a human?) can never solve. The chapters of the book are for the most part independent which makes it easier for the reader to read topics that interests her. Chapter 10 summarizes the whole book.

The section on quantum theory deserves special mention. Yanofsky spends 38 pages describing the world of quantum mechanics. But rather than telling the life stories of the founders of quantum theory (too easy, too boring) or trying to teach the math behind quantum theory (too hard), Yanofsky goes through seven or eight experiments in quantum theory and tells us what the results of the experiments show about the universe and our knowledge of the universe. Included in this is the mysterious topic of entanglement and Bell's famous inequality. I had to read that part twice but I can proudly say that I understand it now.

After reading the whole book, my favorite part is the last chapter. Here everything magically comes together in an amazing way. In the first part of the chapter, Yanofsky gives a four-part classification of all the limitations discussed in the book. Within this classification he makes fascinating links between various limitations in different areas. He connects NP-Complete problems and the butterfly effect; the Halting Problem and the barber paradox; language paradoxes and mathematical limitations. From this "high" point of view, all the different limitations fit together perfectly and one can clearly see the whole beautiful landscape.

One of the central ideas in the book is the concept of self-referential paradox. This is a paradox that comes about from a system that can talk about itself. In chapter 2, the liar paradox is shown to come about because English sentences can talk about English sentences. In chapter 3, there is a discussion of time-travel paradoxes (as in the Back to the Future movies) which come about because events that happen because time traveler can make events that affect themselves. Turing's Halting Problem is shown to come about from the fact that programs deal with programs (as operating systems do.) And Gödel's famous Incompleteness Theorems comes from that fact that mathematics can talk about itself. These are just a few of the more famous self-referential paradoxes mentioned in the book. They form a thread that shows that the same scheme of reason is playing a role in many different areas.

There are some philosophical parts of the book that I cannot truly judge. In chapter 3 there is discussion about the problem of identity (to what extent is something the same even when it changes) and the problem of personal identity (to what extent is someone the same even when they change? What makes a human being a human being?) In chapter 8 there is a discussion of the problem of induction; the "unreasonable effectiveness of mathematics" and the anthropic principle. In these philosophical parts of the book, Yanofsky makes some cogent arguments about different issues. Not all his arguments are totally convincing. I like the more scientific and technical parts of the book where it is easy to tell who is right and who is wrong.

I must mention Yanofsky's style. The writing is crisp and totally clear. Although I learned about the Halting Problem when I was in school, I never truly understood Turing's proof of why no computer can ever solve the Halting Problem till I read Yanofsky's proof. There are also some very helpful charts and diagrams. There are a few Venn diagrams that show different classifications. The book is also very funny. There is a sprinkling of some very clever lines that make it a pleasure to read. The footnotes are also full of such hilarious gems.

A coworker told me that this does not surprise him since he read a textbook coauthored by Yanofsky titled Quantum Computing for Computer Science. My coworker said that it was the only book on quantum computing that one can read without a PhD in physics. He said that book was also very clear.

This book is not hard to read. It is beautifully written in a very understandable way. The reason why the book is fascinating is because it has so many diverse topics. And yet, Yanofsky manages to connect all the topics. This book will get you to think about what we can know about the universe in a totally new and exciting way.

Comment Re:24h clock (Score 2) 309

Half a pint, a quarter of an inch. It is much easier for the human eye to split something into halves than tenths.

Um... You know you can have half a metre, half a centimetre etc, right? Or 1/4 of a metre etc.

Which makes it much easier to figure out what 1/16 of an inch is compared to 0.1 cm.

1/16th isn't a standard fraction of an inch. The only thing below inches is mils, or thousandths of an inch which is metric. You could just as easily have 1/16th of a centimetre if you wanted to.

You can't convert 1 mm to cm exactly in floating point

I tried dividing 1 by 10 in the Windows calculator and it got the right answer without any rounding errors. Apparently computers are capable of performing this calculation. In any case, Imperial measures have exactly the same problem - you can't represent some of the integer ratios used there either.

On top of that this is a complete non-issue. CAD packages don't use multiple units internally, they work in a small base unit which is usually represented as an integer to avoid the kinds of issue you mention. They might, for example, choose micrometres or nanometres. Displaying measures in mm or cm or m is just a case of adding a decimal point in the right place, and stripping the zeros off the right hand side.

If the package wants to use Imperial measures it will probably have mils as the base, which is of course 1/1000th of an inch and as such impossible to convert using floating point maths, so there is no advantage. In fact there is a disadvantage because you can't use the decimal point shifting trick when dealing with units larger than an inch, due to the non-decimal ratios.

Comment Re:24h clock (Score 3, Interesting) 309

The problem is that "12PM" refers to both the moment that is mid-day, and the hour long period between 12:00:00 and 12:59:59. If you think of it as a period then "12PM" makes more sense, since it takes place entire in the afternoon. 24 hour time is obviously much clearer and easier.

I have seen some places in Japan that advertise being open until 27:00, meaning 3:00 the next day.

Comment Version problems and vendor incentives (Score 1) 168

One of the problems that has to be solved is the version-combo problem.

For example, a given project may require version 1 of the database, version 1.5 of the language, version 2 of the OS, version 3 of the middle-ware, version 3.5 of Apache, etc etc etc.

Most cloud services don't support enough versions to handle specific matches, making swapping vendors difficult. You have to change versions to move your project, which often creates bugs and reprogramming effort when you move.

Also, there is no incentive for cloud hosters to make swapping/migration easy; because if they make it easy, you will leave them. Easy come, easy go. They thus pull various tricks and gimmicks to lock you in.

For example, they may give you a nice GUI/web console to make changes to configurations, but there is no accessible file version (or standard) of those config settings such that one has to manually re-configure any new hosting environment to match the old one.

A de-facto "file config police" has to be created somehow to create, enforce, and test such standardization, and vendors will resist using FUD.

Comment Re:Liars, liars, pants on fire (Score 2) 301

Sinn Fein are the political wing of a terrorist organization, and negotiation with them worked out pretty well. The Taliban are terrorists but if we ever want to sort Afghanistan out we will need to negotiate with them.

The argument that it encourages terrorism is stupid. Clearly you have to be pretty badly repressed, far worse than the average UK citizen is, before you are willing to murder other people and possibly die doing so. The fact that if you and many others organized into a coherent group (so there is something to negotiate with) and run a sustained campaign with the backing of significant numbers of ordinary people you might just get to sit down and talk to the people you have a problem with doesn't really enter their minds.

Comment Re:Stop Dismissing this with False Equivalencies (Score 1) 537

While I'm not saying SA isn't a misogynistic culture, you are not factually correct on some points. For example:

* Women in Saudi Arabia are not allowed to drive, on pain of severe punushment.

According the BBC women have been driving openly in protest for a few years now, and on the 26th of this month a mass protest is planned.

The BBC has done some excellent documentaries on SA. I don't know if you can watch them, but what it boils down to is that while there are many human rights abuses and things that seem extremely primitive to us the situation is also far more complicated than many people imagine. For example, the mass protest is being organized on Facebook, and women post videos of themselves driving on YouTube. A lot of people assume those sites are completely inaccessible in SA.

Submission + - The Single Best Overview of What the Surveillance State Does With Our Private Da (theatlantic.com) 1

Lasrick writes: Conor Friedersdorf at the Atlantic writes up a new report (and infographic) from NYU's Brennan Center for Justice: 'Enter a new report published by Brennan Center for Justice at New York University Law School. "What the Government Does With Americans' Data" is the best single attempt I've seen to explain all of the ways that surveillance professionals are collecting, storing, and disseminating private data on U.S. citizens. The report's text and helpful flow-chart illustrations run to roughly 50 pages. Unless you're already one of America's foremost experts on these subjects, it is virtually impossible to read this synthesis without coming away better informed..

Comment Re:Again (Score 2) 214

Like how we were told if there was a fire to first order a pizza, then tell the firemen to follow the delivery to the fire. A lumber yard caught on fire one night, and we watched as the sirens and flashing lights on the fire trucks zig zagged around the neighborhood - 45 minutes later, the fire was out and they still hadn't found it.

I can't believe such an obvious lie was modded up to +5 insightful. Ignoring the rest of your post which may or may not have merit, this kind of stuff is obviously nonsense. At best you were probably confused and the emergency services were attending other events.

Japan has some of the most detailed city mapping the world. Long before Google started doing it their sat-nav systems have full street level 3D views with texture mapped buildings and landmarks, even street furniture. It was quite remarkable being able to drive along and see foot bridges appear on screen as they appeared in front of your car. Naturally all emergency service vehicles, as well as taxies, have access to this kind of technology.

The only hitch is that addresses in Japan can be a bit odd, but we are only talking about once you get down to a single block level. If a lumber yard was on fire they would have been able to see the rising smoke, if nothing else. The idea that the yard wouldn't have been signposted in some way is laughable too.

TEPCO shouldn't be allowed to run anything, but there is no need for this kind of borderline racist nonsense.

Comment Re:Vehicle next door. (Score 1) 233

You don't have that much control. It works the same as the automatic parallel parking systems we have had for a few years now. The space has to be considerably larger than necessary for a human driver to squeeze in, and the computer will always leave a fairly large space in front and behind. Otherwise the person in front might not be able to get their shopping into their boot (er... trunk I think you call it in the US), and neither would you if it was too close to the car behind.

I imagine the minimum allowable space between cars is the distance the door swings open. The one positive thing is that it might encourage car park designers to have reasonable size spaces.

Comment Re:Why? (Score 1) 219

Actually my number one complaint about Samsung phones is the slippery back that makes them hard to grip. HTC have some kind of rubber-like plastic that gives up plenty of grip. I always fit a minimal "shell" case for this reason.

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