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Albert Frank (founder)

I was born in 1943 somewhere on the hidden face of the moon;-)
In 1965 I had a master degree in mathematics (option: physic, general relativity) at the Liège University (Belgium).
I became a chess master and won the 1968 Brussel's chess championship.
From 1966 to 1994, I was a teacher in universities in seven different Central Africa countries. I made several researches. A summary of the main ones can be seen at http://users.skynet.be/albert.frank/chess_and_aptitudes.htm

Unfortunately, it could not become a Ph.D. because it was obligatory to have other diplomas in the same field, and I was only an autodidact in psychology, as the mathematician of the faculty of psychology of the national University of Zaïre.
I was also, among a lot of hobbies, flight instructor, bridge player and puzzles creator.
I have been chess champion of these 7 countries (the level was not very high;-)
In 1994, I had to escape from Rwanda, when the horror started there ...and I lost a lot of works I had done.
I came back to Belgium. I found a job as statistician in a ministry - boring ;-)
I retired a few months ago.
I joined first Mensa, then Glia (the 3 s.d. Society created in Holland by Paul Cooijmans).
I'm now member of about 25 high iq societies, including The Sigma IV Society (old norms), The Pars Society, The Prometheus Society (subscriber), The Pi Society (subscriber) …

In March 2000, I took the initiative to invite in Brussels several "top IQ people", including Nik Lygeros and Philippe Jacqueroux. It was a fantastic meeting. After that, there where several meetings in Paris, Seattle, Sao Paulo and Curitiba.

In all of these meetings, the great thing was the communication among the participants. I think I was very lucky to meet so many great human people. Several became big friends. A direct communication is totally different from an e-mail communication.

I have written about 50 articles, and NATAN, a book in connection with communication: http://www.lulu.com/content/71060.

My favourite authors: Einstein, Kafka, Stapledon, Hofstadter.

My favourite films: Citizen Kane, Cabaret, Les enfants du paradis.

Particularity: I have no television;-)

"Everybody does it" is not a reason for doing it.


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Peter Bentley  (co-founder )

It  all began  with the  classic  12  coin  (or  12  ball)  puzzle  -  I  am  sure  you  know  it : one  coin/ ball  is  a  little  bit  heavier  or  lighter  than  all the  others,  and  you  have  to  find  that  coin/ ball and whether  it  is  lighter  or  heavier    with  three  weighings   on a  balance .   A   Chinese   friend   gave  me this  puzzle  several years  ago  and  after  several  hours  I  decided  it  was impossible to solve  and  so I  asked for  the solution.  I  was  SO ANNOYED   when  I saw  how   beautiful   the  solution  was    that  I  decided  to  start  finding  other  similar   “beautiful”   puzzles to share  with  my  Chinese  friends  I  should  explain  that  I  have  lived  in HK    since   1981  and  I  work  mostly  in China  The  only  restriction  I set  myself  was  that  all the  puzzles  should  be  based  on  PURE  LOGIC :  that means  no  special  knowledge  of  English  or  western  history/ culture   (nor  even  Roman  numbers  like  IV =  4  )  should   ever  be    required. The  puzzles  should  be  equally  easy (difficult) to solve  for anyone  who  can read  and  write  basic  English.    Also no advanced   maths knowledge should be needed.  However   this  was  in the days  before  I  started  to  use the  internet  so I  soon  ran out  of  puzzles.   I therefore   placed an advert in Mensa Intl.  to  find  others  interested   in exchanging  puzzles, and  among  the  replies  I  got  was  one  from  Albert,  attaching a  selection  of  his  wonderful  puzzles  collected  and  written  by  him over the  years.

 This  started  what  will surely  be a  lifetime  friendship  with  Albert,  and  led  on to  us starting  (or  rather  RE- starting)  Ludomind.  I  confess  I  have  taken the  back seat  and that  Albert  has  done – and  still  does  do  -   99%  of the  work,  the  reason being  that  I  am   not  retired  like  Albert, so I spend most of  my time  traveling   in China where  I sell  specialist  vacuum  instruments :  mostly leak  detectors  to  refrigerator and  air –conditioner  companies,  but  more  recently  also  the  world’s  first  and  still the   world’s   only  PORTABLE  GC/MS    (   and  if  you  know  how  big, heavy  and  fragile   a  GC/MS  is  it’s  worth  setting a  puzzle  just    to  answer   how  it   can  be made  portable!)  .


A high  point  in the relationship  between  Albert and  me  was  doing the  Sigma  Test  which  Albert  introduced  to me.   I am  not  a  great  fan  of  IQ tests , most of which  seem  deadly  boring .  I  only  just  managed  to  get   into  UK  Mensa  about  30  years  ago  by  scoring  the   minimum IQ for admission  (if  I recall  correctly  it was  148  on the  Cattell  scale )    in  a  timed   examination  test  set  by Mensa  in London , and that  was only achieved  by buying  several  Mensa  test  papers  and  learning the  methodology  of their   test  questions.   So  my  IQ  must  be  pretty  low  by  Mensa  standards  -  or  at least  Mensa  test  methods.  However  the  Sigma  Test  is something  completely   different   First:  the  questions   near  the  end  are   so  interesting  that  they  almost  demand  to  be  attempted .  Secondly  there  is  no time  limit, and  I  always  achieve better  results  when  I am  not  under  time pressure.   The  questions  in the  middle  about   lines , triangles  etc  seemed  rather   difficult and  very   boring,  so    I  didn’t   bother  to  try  them until  one  day  I  got a  badly   infected  finger  and  had  to  go  to  hospital  for  3 days  of  continuous  intravenous  antibiotics.  I HATE  HOSPITALS  AND NEEDLES……… so  I  distracted  myself  by working  non  stop  on all the  middle  questions  in  the  Sigma Test    and   thinking   more  about the  later  questions, especially  Joao  and the  egg.   On coming out of  hospital  I  found  2  completely  original  solutions to the  egg  question that  even  Melao  didn’t  know   were  possible, and  were  not  precluded  by the  rules  as set at that  time.  So   Melao  (via  Petri  Widsten  with  whom  I was  corresponding  in English)   gave  me  another  chance   and  in doing  so  tightened  up the  rules  of the  question to  prohibit  my original  2  solutions.  Eventually  - I am  happy   to  say  -  I  did  find the perfect   solution . I   never  solved  Q35  - the  one  about the  aliens  (only Petri ever  solved  that  and  it  seems  no-one  except  he and  Melao  know the  answer !).    But  all that  work  on the  Sigma Test  took me  WEEKS,  which  proves  that  perseverance  goes  a  long way, even  if  one’s  IQ  is not so  high .  I    do  have  a  D. Phil.  (= Ph. D)  in  low  temperature  vacuum engineering  from  Oxford    University, but  when  people  commend  me  on  it  I  simply say  that  there  are  only  two  qualifications  to  get  a  D. Phil  :  “to  be  stupid  enough  to  start and  to  be  determined  enough  to  finish :  intelligence  has nothing  to do with  it”   - which  is  true !   Even  now  on Ludomind,  I  take  on  average  5   -  10  x  longer  to  solve  puzzles  than  super  solvers  like  Philippe,  Albert,    Edward, Luis   and  others.  But  the  time  spent  working  on the  solutions  is  so  enjoyable  that  my  time  spent  on  aircrafts and  in   taxis in China  is  pure  joy.


To my mind, the   two great things about Ludomind are that:

1. The puzzles are indeed truly pure and beautiful!

2.  The  group  is    very  small  and  friendly  so that we are  able  to  correspond  with the  puzzle  authors  to  get  hints  and  discuss  puzzles  privately. This means  we never  are  faced  with  the  dilemma   which  my  Chinese  friend’s    12  coin/ball  puzzle  gave  me  all those  years  ago :   “ Do you  want  the  solution ?  Here  it is  - take  it  or leave  it !”  If  you  look at  the  solution  you  can never  have  the  fun of  solving  the  puzzle  yourself  again , and  if you  don’t look  at   it you   will  never  know  the  answer.


 It  is   possible  for  everyone  on  Ludomind  to  discuss and  get hints  from the  author  until  one  finally  has the  satisfaction  of  finding the  solution  oneself, hoverer long it takes.   I  had  great  fun   exchanging  emails   with Philippe  on the  “Sultan  of  Brunei” puzzle   and  also  with  Albert  on his  recent  chess  puzzle (1/2006)  until  I finally  got  the  solutions.  If  I  had  not  been  able  to  discuss  with them  I could  never  have  found the  real  solutions,  and  if  the  only alternative  to  giving  up  was to  look  up the  solution  on the  website  (like  so many  other  puzzle  websites)  I  would   be  SO ANNOYED  at  myself  for  not  continuing  to  try  until  I  did   find  the  solution  ………..which  takes  me back to  the  beginning and  the  12  coin/ball  puzzle. Just  for  the record,  I  did  finally solve  this puzzle   on my own   because  Philippe  extended  it  to  13  coins  (not  balls  - that’s  a small  hint ! )  and  in solving  this  extended  puzzle .  I  found  the  beautiful  “general”  solution  to the  12  coin/ball  puzzle  (  It  turns  out  that  this  puzzle   is  well-documented  on the  web.  There  are  3  solutions :  2  are  “consequential”  i.e.  the  each  weighing  depends  on the   result  of the  previous  one,  and  the  3rd  is  the   “general”  solution  where  the  3  weighings  can be  done  in random  order.  My Chinese  friend  only  showed  me  one  of  the  2  “ consequential”  solutions . )



Well that’s   all   about  me!  There’s not much more  to add.     I was  born in  1948,  educated  in  UK  (Bristol  and  Oxford)  and     I  have  lived and  worked  in Hong Kong  since 1981 .  I speak  German  and  Chinese. My  wife  is  Chinese  (we  met  at  Oxford  University  ) and  judging  by  how  fast  she   answered  a  Mensa  test  paper  which  I was  studying   in preparation for  the  London  Mensa  exam  all those  years  ago  her  IQ  must  be  >180   Many of  the  Mensa  questions  require  good  knowledge  of  English  and  English  is  her  SECOND  language !   We  have  no  children  , but  we do have  8  persian  cats,  one of  which  has  an IQ    of  at  least   190  on the  Bentley CatTail  scale  : the  most intelligent  cat  I have  ever  known  Incidentally, and  curiously   -  he  is  a  midget  cat  : half  the  size  of all the  others.   So far  I have  not  taught  him to  play  chess   but  I am working  on it.   He  prefers   to  knock  the  pieces  off   the  board   one at a time   rather  than  move  them around……

LokLok - a cat with IQ200 on the CatTail scale

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Guilherme Marques dos Santos Silva  (member and webmaster )

Guilherme was born in 1973 in Brazil.

His interests are various: mathematics and physics, aviation, paragliding, civil engineering, education, puzzles.

He graduated in civil engineering and math, and now teaches math and works in projects regarding algorithms.

He developed an algorithm to calculate optimized routes, which drastically reduces processing time, and will probably soon be used as part of the controlling system of integrated transportation (trains, buses, cars and pedestrians) in Holland.
He is member of some high IQ societies:
Glia Society, Ludomind Society, Epimetheus Society, Sigma Society, Prometheus Society - subscriber, Platinum Society, Colloquy, Mensa Brasil and Mensa International, Puzzles Math (owner).

In July, 2004, he was the winner of  the Fourth International Contest of Logical Problems, from Ludomind.


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Hindemburg Melao Jr.

Chessmaster, holder of two World Records in Chess.

Teacher and Analyst of Chess.

Author of The Sigma Test,Sigma Test VI.

Author of many articles-papers about Chess, Mathematics, Psychometrics.

Founder of Unicorn High IQ Society.

Founder of Sigma V, Sigma IV, Sigma III, Sigma.

Honorary Member of HIQH, Life Member of IHIQS, PARS Honorary.



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