MU puzzle

Post by starbeast » Sun, Dec 16, 2018, 2:42 AM UTC

chongli wrote: post #5

lixtra wrote: post #4

When I read about it in Gödel Escher Bach I wasn’t aware yet that unsolvable is a valid answer to a problem. I felt cheated(1) and the whole book lost a lot of its appeal. In retrospect it may have actually undone some damage done by the school system where the solution space is usually very restricted. Edit: (1) From what I remember it’s stated as find the sequence and not does such a sequence exist.

I would continue arguing that "unsolvable" is not a valid solution to this puzzle . If the description asks you to "find the solution" and the solution does not exist, then it is a riddle, not a puzzle.

Post by muthdra » Sun, Dec 16, 2018, 3:51 AM UTC

haskellandchill wrote: post #18

amatic wrote: post #14

Is the Gödel Escher Bach worth the reading? I started, but I feel it's fluff. People say he is good, though. Are there some practical insights?

No it’s fluff, good for curious people with no background.

Post by justinator » Sun, Dec 16, 2018, 4:00 AM UTC

edflsafoiewq wrote: post #20

amatic wrote: post #14

Is the Gödel Escher Bach worth the reading? I started, but I feel it's fluff. People say he is good, though. Are there some practical insights?

I think most of us who really like it read it as kids which colors it too much. I distinctly remember this proof that you can't solve the MU-puzzle as the first piece of mathematics I ever saw. In one swoop I discovered impossibility proofs, invariants, and the use of divisibility which suffused the whole book with an aura of initiation into great mysteries that it will never attain for the already-initiated.

    #!/usr/bin/perl -w
    use strict; 


    my %tried = (); 

    main(); 

    sub main { 

        my @rules = (
                     \&rule_one, 
                     \&rule_two,
                     \&rule_three, 
                     \&rule_four,
                    ); 

        my $axiom = 'MI';
    
        my @path; 
        my @tries; 

         solve($axiom, \@rules); 
    }


    sub solve { 

        my @app; 


        my ($axiom, $rules) = @_; 
        my $i = 0; 

        foreach(@$rules){ 
            my $tmp =  $_->($axiom);
            push(@app, $tmp) if $tmp;
        }

        foreach(@app){ 

            next if $tried{$_};
            next unless (length($_)