intemporaliter  and I will be flying back to Edinburgh Friday evening, and leaving Wednesday morning.

Who is out and about Friday night? Late night at the pub?

So I was talking about a short story that included time travel last
night and the conversation connected a bunch of useful things about
precognition, and I have expanded that here.  This post has math, but
simple math, and computer science, but simple computer science, and
magical oracles, but simple magical oracles.

In the story the future and past could be visited and objects and
information exchanged, but the events could not be changed.  Another
possibility was brought up, inspired by another story: if you could
see your future and actions then you would see the best possible
future since otherwise you would do something different.

Of course that depends on your actions converging.  Consider your
decision as a function F which is applied to the action X you see your
future self performing. The output of F(X) is the action you choose to
perform after seeing action X in your future.

Then there may be a "fixed point" where you see X and still decide to
perform X, because X is obviously the best action to take. I can write

X = F(X)

Now substitute F(X) for X in the right hand side:

X = F(F(X))

X = F(F(F(X)))

X = F(F(F(F(F(F(F(F(....))))))))

So now one can see how to, perhaps, construct X from just F.  The
above infinite nesting of F computes what is named the least fixed
point.  Most programming implicitly or explicit works like the
infinitely nested F, basically because it allows the program to have
loops and recursion.  [ side note: I will not discuss the "Y
combinator" here ].

But consider this F: "if you see yourself turn left then you decide to
turn right, and if you see yourself turn right then you decide to turn
left."  This will never converge to a stable answer.  Similarly, some
programs never halt — they will loop forever and never have a stable
answer.

In some stories, what you see in the future (or learn from time
travel) affects the future in this recursive way.  Sometimes this
looping is explored iteration by iteration (Back to the Future), and
sometimes just the fixed point is experienced (the unchangable past
and future).  Stories with multiple parallel worlds/futures will not
concern me here.

Considering finding the fixed point to precognition led me to the
capsule summary of Turing's Halting problem (1936).  If some programs
(algorithms) halt and others do not halt then how can you tell the
difference?  The traditional nomenclature is that a Turing machine has
a HALTING STATE which it either reaches or does not reach.  Some
programs obvious halt, some obviously don't: can one write an program
(algorithm) that reads programs and decides if they halt?

Let us suppose such a program CHECK_HALT existed.  This would be a
little like precognition.  CHECK_HALT will read an input program & the
data it would be run on and tell you whether running that input
program on that data will eventually halt or will run forever.
CHECK_HALT "predicts the future" halting of the input program run on
the data.  Note that it cannot actually run the program on the data
because the program & data may never halt but CHECK_HALT is supposed
to always halt.  Thus CHECK_HALT has to be much more clever than just
simulating the future running of the program.

Now I could write a program P with this supposed CHECK_HALT as a
subroutine.  This P will read a program Q as input and then run
CHECK_HALT on input program Q & data Q.  Then CHECK_HALT will cleverly
simulate running Q on Q.  If CHECK_HALT says the input program & data
never halts then P will decide to halt, if CHECK_HALT says the input
program & data halts then P will go into a loop and never halt.  This
is analogous to the left versus right turning paradox given
above. Program P will do the *opposite* of what the input program Q
would do.

What happens if P is run and fed the program code for P itself as
input?  Thus Q is P and P does the *opposite* of what P would do.  Now
look closer. P passed the code for P & data P to the CHECK_HALT
subroutine.  If the CHECK_HALT subroutine says P on P would halt then
P decides not to halt.  If the CHECK_HALT subroutine says P on P will
not halt then P halts.  Either would lead to a contradiction, lead to
a paradox.  All this trouble comes from using CHECK_HALT to simulate
itself as part of program P: I see myself predicting left, right,
left, right...

So to avoid paradox, the assumption that CHECK_HALT is a program that
always tells the truth and then halts must be false.  Thus:

 * CHECK_HALT may not be a program; it may be some infinitely wise and
transcendent "oracle", and I really do mean infinite

 * CHECK_HALT may be wrong (tell a lie, make a guess, etc.) about
whether the input program & data halts

 * CHECK_HALT may decide that the only possible thing it do when run
on program P & data P is to refuse to give an answer by never halting.
And thus running P with input P will never halt, but this time because
CHECK_HALT goes into an infinite loop.  So CHECK_HALT has some inputs
that cause it to loop.

Thus every single clever analysis program CHECK_HALT has at least one
input that it refuses to classify.  You cannot beat the logic.  In
analogy to precognition and time travel: Maybe this means that people
who insist on being contrary — like in the left and right turn example
— would encounter such a non-answer and fail to see the future to
being with.  Maybe people who would go back and kill their grandfather
would never be able to time travel (or would travel but never arrive).

Thus the future in such a story is only "clear" when it will go
unchanged — either no changes will be attempted or all attempts to
change it are doomed to fail.  So cryptic oracles that lead the
listener to ironically fulfilling the prophesy fit in just fine.  One
could still make a fortune betting on sports or buying lottery
tickets.

Also: if you had CHECK_HALT you could check any mathematical statement
EQ to see if can be proved.  Write a program LOOK to start with the
axioms and brute force search all derivations from them until EQ is
found.  If CHECK_HALT on LOOK says that LOOK halts then EQ must be
provable.  If CHECK_HALT on LOOK says that LOOK never halts then EQ
cannot be proved.  This is more than a bit like information for free.

But time travel stories also can feature information for free.  The
story last night had the older self tell the younger self where to dig
up buried treasure.  How did the older self know?  He was told when
younger.  [ And even geekier: In Star Trek, who invented transparent
aluminium ? ]

Calling CHECK_HALT and "oracle" is not new thing, the father of
CHECK_HALT named it thus: "[Turing] imagined a God-like computer, much
more powerful than any real computer, which could know the unknowable:
whether a real computer would halt when running a particular program,
or carry on forever. He called this fantastical machine an "oracle". [
http://www-2.dc.uba.ar/profesores/becher/ns.html ]

What is even worse is that mathematician Gregory Chaitin has defined
the Ω number, which is essentially "the probability that a randomly
chosen program halts".  Thus Ω is a well defined real number between 0
and 1, and we can compute the first few decimal places.  But it is
provably impossible to be completely computed; any attempt will reach
a decimal place where one gets stuck.  The answer for the further
digits cannot be obtained from our axioms of mathematics.  But
Turing's "oracle" machine knows Ω...

So there are things in mathematics that mathematicians can never see,
many things.  If we want to know more digits of Ω there is a simple
program O that never halts: as it runs it starts at 0 and the output
rises getting close and closer to Ω, but never reaching it.  Without a
magic "oracle" we can learn more about Ω, but we can only learn it by
running such a program like O and waiting for the
future. "Precognition" of the rest of the digits is logically and
provably impossible, one must grow old instead, and even then the new
digits are not known for certain...

The subject is not a joke: "I brought some. Here I'll let them roam around. There is no reason only poor people should be infected."

For those not a the conference, Bill gave you plenty of bugs already — just run his software.

I saw this via dailykos, who saw it at foreignpolicy, where this is Tacitus's Annals, book VI.

" First, the Twelve Tables prohibited any one from exacting more than 10 per cent., when, previously, the rate had depended on the caprice of the wealthy. Subsequently, by a bill brought in by the tribunes, interest was reduced to half that amount, and finally compound interest was wholly forbidden. "

So they decreed an artificially low interest rate.   This caused problems.  Credit was largely backed by property...

"Hence followed a scarcity of money, a great shock being given to all credit, the current coin too, in consequence of the conviction of so many persons and the sale of their property, being locked up in the imperial treasury or the public exchequer. To meet this, the Senate had directed that every creditor should have two-thirds his capital secured on estates in Italy. Creditors however were suing for payment in full, and it was not respectable for persons when sued to break faith."

A credit crisis.  The government seems to have seized a bunch of property and creditors with claims on this were not happy at getting 2/3rds of their claim.

"So, at first, there were clamorous meetings and importunate entreaties; then noisy applications to the praetor's court. And the very device intended as a remedy, the sale and purchase of estates, proved the contrary, as the usurers had hoarded up all their money for buying land. The facilities for selling were followed by a fall of prices, and the deeper a man was in debt, the more reluctantly did he part with his property, and many were utterly ruined."

Lack of credit (scarcity of money) means less money available for offers for land, and so property prices fall.  Mortgages are under water, and people are ruined.  Perhaps there was a real estate bubble, perhaps not, but the fallout is the same as now:

"The destruction of private wealth precipitated the fall of rank and reputation, till at last the emperor interposed his aid by distributing throughout the banks a hundred million sesterces, and allowing freedom to borrow without interest for three years, provided the borrower gave security to the State in land to double the amount. Credit was thus restored, and gradually private lenders were found. The purchase too of estates was not carried out according to the letter of the Senate's decree, rigour at the outset, as usual with such matters, becoming negligence in the end."

Give huge bailouts from the government to the banks — check.
Lower the official interest rate to zero — check.
Attempt to obtain some kind of property as collateral — check.
The collateral obtaining was mired in corruption and negligence (lack of government oversight) — check.

The good news: Tacitus thinks it worked out in the end.

And as Rick at foreignpolicy points out the above is followed by:

"Sextus Marius, the richest man in Spain, was next accused of incest with his daughter, and thrown headlong from the Tarpeian rock. To remove any doubt that the vastness of his wealth had proved the man's ruin, Tiberius kept his gold-mines for himself, though they were forfeited to the State."

Falsely (?) accusing a man named Sextus of being pedophile is not being very subtle.

I'll post this as public so I can send links to others.

Obama has promised to implement some kludged form of universal health insurance in the USA. So the opponents are again coming out in force to scare the public into opposing the idea. The latest from ABC news (one of the big 3 networks) is
I am surprised they did not autoplay spooky music when you visit the article.
It is tricky to copy and paste an example of the scare-mongering since every sentence could do. It starts :

Imagine a country where the government regularly checks the waistlines of citizens over age 40. Anyone deemed too fat would be required o undergo diet counseling. Those who fail to lose sufficient weight could face further "reeducation" and their communities subject to stiff fines. Is this some nightmarish dystopia?

No, this is contemporary Japan.

And it ends:

If we still value our freedoms, we must reject both the nanny state and universal healthcare. Otherwise, it won't be long before the "Waistline Police" come knocking on our doors.

Of course the current private health insurance system will
  1) Deny to cover people it thinks are too unhealthy or will drop coverage if you get too sick.
  2) Usually not pay anything to treat problems that you started having before the insurance coverage.
  3) Charge people more money based on their lifestyle or other other factors (especially smokers).  But since this is not a stiff government fine, it is the private sector.
  4) Try to avoid paying anyway, and drop you if you get too sick.
And, of course, Americans pay more for the same healthcare than anyone in Europe or Japan.

In all the disappointing prop-8 fallout, I have run across one good satire: defining Christmas.

Hmmm...I'll make this post public.

I will vote for the democrat, but I have changed my mind about contributing any money.

I found this the other day when looking for pirate-y music for collegecate, and now I found some audio on youtube and must share:

"Doctor Who and the Pirates (Or The Lass That Lost A Sailor) is a Big Finish Productions audio drama based on the long-running British science fiction television series Doctor Who. It is also the first musical story in the series' history."

There features "I Am the Very Model of a Gallifreyan Buccaneer" (lyrics) (youtube)

Four word movie reviews, such as

Best In Show (2000) 'This Is Spaniel Tap'
Bridge On The River Kwai, The (1957) Big bridge goes P.O.W.
Pirates Of The Caribbean: The Curse Of The Black Pearl (2003) High-sea dead people.

deathlyphil  asked in the comments to my last post:

I can't believe someone could write something like and not realise how offensive they were being.

What I don't understand is why America holds on so tightly to its history of slavery. Britain had slavery, so did France and most of the other major European powers. So why have we moved on and America hasn't?

I do not know much of the sociology, not the foreign histories. But consider: In the New World, slavery was nearly identical to being (descended) from Africa. Legally, the "one-drop of blood" rule was applied to define negro. But most important is the percentage of residents who were slaves, and the way this made (southern) American culture much more affected than British.  Americans older than, about, me were born in a violently racist country. And, I end this post with an account of the two high schools where I grew up.

In the second census of the America in 1800, I see in order of total population:
etc.

So there were clearly two kinds of societies in USA. In 1800, 18.9% of the people were black, of which 89.2% were slaves. But from the state data above, you can see this 18.9% were very clumped in the slave states where ~40% (or more) were slaves and ~60% were free.

By comparison, in Britain I can find only the estimate that in 1772 (Sommerset court decision), that there were 14,000 to 15,000 blacks in Britain. In the 1801 census, the British population was over 8 million. So the density of slaves in 18th-19th century Britain seems much less than 1%. The British moved slaves to the New World, and owned them in the colonies, but British culture in Britain was never one of slavery in the way that was established in half of the USA.

At one time it was normal for the state and (e.g. Baptist) church to encourage feeling morally entitled to rule over such an ethnicity. To go from that power structure to being democratically equal is an enormous change; now in southern states about 1/3 of population is African-American. Restraining the slaver-owners and the descendants by force took the bloodiest was in USA's history followed by a century (5 generations) of inequality before the 1960's civil rights acts, which created another wave of violence and enforcement which has taken about 40 years (2 generations) to lead to the present day — where about half of the half of the country (i.e. half of the democrats) have chosen a half-African as Presidential nominee.

This is the ethnicity that started off, at abolition, as a huge percentage of the local population and remains the biggest (12%). Others, e.g. hispanic (9%) and asian (3%), started off and remained smaller — and were not previously slaves.

Those opposed to helping blacks are naturally opposed to government programs that help the poor — this is one reason behind the lack of universal health care in America. The desire to segregate drove much of the urban flight of whites to create the suburbs. Defending that housing segregation lead the riots mentioned in my previous post.

I went to a mostly white high school with 2582 students: 58% white, 26% black, 14% hispanic, 2% asian. The other high school in my city of 75,000 (26.6% black) was 2101 student: 8% white, 46% black, 45% hispanic, 1% asian. That's from careful drawing of the school district line to follow the segregation of the housing. How fair do you think the housing market has been for the last few generations? How equal do you think the education at the two high schools is?

As many of you are not Americans, and most of you are even younger than I am, you may learn even more from "The Meaning of Box 722" than I have. The post has something I have never seen published before: copies of the letters people mailed to their congressman, in this case in the mid-1960's. It's what people had to do before blogs and e-mail.

We are writing to you, and requesting legislation for a repeal of the Civil Rights Act of 1964.
The Act wil rob a great many Americans of their rights to property, individual liberty, freedom of choice, and enterprise.
This Act is the wrong vehicle, impracticale and undesirable, and we are bitterly opposed to it.
We also request legislation to stop these civil rights demonstrations.

Bits I (re)learned from the linked post:

• Racism in America is not just in the South
• Civil rights laws caused massive and violent counter-demonstrations by urban and suburban whites:
  

  Three days later 600 marched again in Chicago, against 10,000 counterdemonstrators. Some wore Nazi helmets. Others waved Confederate battle flags, carried George Wallace banners, Swastika placards that helpfully explained, "The Symbol of White Power." This was the famous march where Martin Luther King was hit by a giant rock, where he told the press, "I think the people of Mississippi ought to come to Chicago to learn how to hate,"...

• Note that the main issue in the linked post is a law just about non-discrimination in rental and sale of housing, and is still the law
• Passing and enforcing laws that allowed African-Americans to vote and have such fair housing destroyed the popularity of the Democratic party from that moment to the present day

If Barak Obama gets elected then this period of time of over 40 years and lasting two generations will have ended. No problems will be solved by the election itself, but the opportunity will once again appear. I hope the mixed bag of democratic politicians will make progress. Perhaps this generation will handle it better.

To get elected, the torrent of evil and stupidity in the media, such as todays opinion piece in the major Washington Post newspaper. This is where the author, Anne Applebaum, pretends to care what foreigners think so that she can put racist statements into their mouths, since she does not have the brazenness to directly appeal to racists in America.

The NYTimes has a article about "A growing body of evidence shows that same-sex couples have a great deal to teach everyone else about marriage and relationships", which is not fantastic — but my expectations regarding such social science writing were so low that an average article appears amazing.

This past Sunday (2008-02-10) was when the group known as Anonymous declared there should be protests outside all the Scientology centers.  I was mildly surprised that such demonstrations occurred, and this prodded me out of hiding to make this post.

The first message from Anonymous to Scientology is on youtube here.  It is quite a treat -- their sense of theater is perfect.  I recommend it.

There are several other such messages, reactions to and parodies of the messages, and clips of news coverage and clips of the worldwide protests all posted on youtube.  There is even a wiki setup at http://www.partyvan.info/index.php/Project_Chanology, which fits into this on the side of Anonymous (as much as a public wiki could, at least).

If you need a refresher on the cult then Operation Snow White is a good start, as is the more recent BBC Panorama row.

From the Los Angeles Times article about Sunday:

Asked to explain the sudden groundswell of opposition to Scientology, Lynn Fountain Campbell, who said she'd been part of the church for 40 years, said, "It's just reached a critical mass. People just aren't scared anymore." 

Cheers.

Bonus limerick:

A woman in liquor production
Owns a still of exquisite construction.
The alcohol boils
Through magnetic coils.
She says that it's "proof by induction."

The NY Times reports that Gail Simone is the new writer for the Wonder Woman comic book, and  "She is the first woman to serve as “ongoing writer” (to use the industry’s term) in the character’s 66-year history."

You will probably want to read this article:

"A number of skulls were also found to have sets of up to three holes at odd intervals, consistent with a blow from a three-pronged weapon such as a trident."

I have done much (non-contact!) larping.  Two weekends ago at conpulsion and last weekend at the student nationals.  So I have been

• A non-mad scientist escaping from a mad scientist in a castle
• One of a group of former (modern day) religious cultists talking things over
  
• A magician running a convention of magicians.  It turned out to be a murder mystery.
• A senator from Terranova (i.e. America) in a diplomatic meeting in 1914 (with fantasy elements)
• The (abducted) president of the united states.  It turned out that it was aliens.

With this much recent larping I could not be anything other than happy.  And yet in no game did I kill anything.

One of the most venerable name generators: The Cyborg Name Decoder

Mine is quite good:

Get Your Cyborg Name

My Peculiar Aristocratic Title is: Emperor Christopher the Flavoursome of Eschaton End Get your Peculiar Aristocratic Title

UPDATE: I have re-enabled mightyreason.com -- Tech support explained what I needed to do!

I have a couple of friends coming to visit me in Edinburgh as of Wednesday morning (through Sunday).  I am soliciting suggestions for the quirkiest things to see or do in the city, big or small.  What caught your fancy?  Why do you like this place?  Where is your secret lair?

As for me, I had fun at HW Gamers on Sunday, though the dodge ball and lifting furniture was more exercise than my gym-less life has been filled with recently.  I had hoped (wrongly) that walking everywhere would keep me in better shape than this...

(62.6% pure)

If my experiments fail, I have been wondering what I might do next.  New idea of the day: apprentice to Gabriele Amorth.  An interview of his is inspirational:


Now faith is the substance of things hoped for, the evidence of things not seen.