From: cet1@cus.cam.ac.uk (Chris Thompson) Newsgroups: sci.math Subject: Re: History of the four color conjecture Date: 1 Sep 1996 17:41:44 GMT In article , Hans Kristian Ruud writes: [...] |> I read the original column, which was published in April 1975 (I think). |> It contained altogether 9 "sensational" items. Among them were also the |> report of a chess-machine, who, by playing against itself, had conclusively |> established that 1. h2-h4 is the best opening move for White. Btw, I was |> among those taken in. Yes, it was April 1975. [Someone else suggested April 1976, but although Gardner's column there does indeed mention the 4-colour problem, it takes off into perfectly serious stuff about non-planar cubic graphs which are not 3-edge-colourable.] There are "six sensational discoveries that somehow or another have escaped public attention", each one widening the credibility gap a little more. They are 1. Counterexample to the four-colour theorem. 2. exp(\pi\sqrt163) shown to be an exact integer by "John Brillo". [This one still turns up on sci.math from time to time as well.] 3. P-KR4 shown to be a winning opening move for White by the computer program "MacHic" designed by "Richard Pinkleaf". [I can't forbear to quote the following paragraph... Bobby Fischer reportedly said that he had developed an impregnable defense against P-KR4 at the age of 11. He has offered to play it against MacHic provided that arrangments can be made for the computer to play silently and provided that he (Fischer) is guaranteed a win-or-lose payment of $ 25 million. Ah, memories...] 4. Logical flaw found in Special Relativity by "Humbert Pringle". 5. Leonardo da Vinci found to have invented the valve flush toilet. 6. Psychic motor constructed by "Robert Ripoff, the noted Prague parapsychologist", and reported on by "Henrietta Birdbrain, an American expert on Kirlian photography". How anyone could get through the last one without the penny dropping is hard to understand... |> In a later column, Gardner admitted that it was an April Fool column. "Admitted" ? He avowed it! It was in the July 1975 issue, with a section that starts The April Fool hoax column produced more than 1000 letters from readers who failed to see the joke in spite of the outlandish names and preposterous ideas. Hundreds of readers sent colorings of the four-color-theorem map. William McGregor, who designed the map as a puzzle, has given me permission to use his name. It is not revealed, however, whether there is really a "Wappingers Falls, N.Y." at which he is resident, as stated in the April issue :-) Many of the names are jokes ("John Brillo" is John Brillhart, etc.) Here's the map, of 110 regions (excluding the infinite one), more or less as it appears on page 128 of the April 1975 issue. (I have changed the proportions a little to fit it into 80 columns. It is cubic, with the vertices being indicated here by +'s.) Good luck with colouring it... /----------------------------------------------------------------------------\ | | +------+-------+-------+-------+-----+-----+-------+-------+-------+------\ | | | | | | | | | | | | | | /---+---+---+---+---+---+---+--+--+--+--+---+---+---+---+---+---+---\ | | | | | | | | | | | | | | | | | /---+---+---+---+---+---+--+--+--+--+---+---+---+---+---+---\ | | | | | | | | | | | | | | | | | | | | /---+---+---+---+---+--+--+--+--+---+---+---+---+---\ | | | | | | | | | | | | | | | | | | | | | | | /---+---+---+---+--+--+--+--+---+---+---+---\ | | | | | | | | | | | | | | | | | | | | | | | | | | /---+---+---+--+--+--+--+---+---+---\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | /---+---+--+--+--+--+---+---\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | /---+--+--+--+--+---\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | /--+--+--+--\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | /-+-\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+--/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | \-+-/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | \-+-+-+-/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | \-+---+-+-+---+-/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | \-+---+--+--+--+--+--+--/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | \-+---+---+--+--+--+--+--+----+-/ | | | | | | | | | | | | | | | | | | | | | | | | | | \-+---+---+---+--+--+--+--+--+----+---+-/ | | | | | | | | | | | | | | | | | | | | | | | \-+---+---+---+---+--+--+--+--+--+----+---+---+-/ | | | | | | | | | | | | | | | | | | | | \-+---+---+---+---+---+--+--+--+--+--+----+---+---+---+-/ | | | | | | | | | | | | | | | | | \-+---+---+---+---+---+---+--+--+--+--+--+----+---+---+---+---+-/ | | | | | | | | | | | | | | \---+-------+-------+-------+-----+--+--+-------+-------+-------+---------+ | | | \---------------------------------------+------------------------------------/ Chris Thompson Email: cet1@cam.ac.uk