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INCOMPLETE_GOEDEL


                                             June 8, 2019                 
                                                                          
There are many and various popular descriptions                           
of Goedel's Incompleteness Theorem.  This one is                          
pretty good, I think:                                                     
                                                                          
https://blog.infinitenegativeutility.com                                    ~/Dust/Attic/Prog/getty_ritter-2018-why_i_dont_love_goedel_escher_bach-infinitenegativeutility.html
                                                                          
    "...  Gödel’s incompleteness theorem. The high-level,                 
    slightly handwavey description of this theorem is                                         https://en.wikipedia.org/wiki/G%C3%B6del%27s_incompleteness_theorems
    that, for any sufficiently expressive mathematical                    
    proof system, there are more true facts within the                    
    system than there are proofs for facts, which in                      
    turn means that not every fact can be proved: in                      
    short, that not every mathematical fact has a                         
    corresponding mathematical proof. My short                            
    explanation papers over a number of important                         
    features of this theorem, such as what I meant by a                   
    ‘sufficiently expressive mathematical system’ ... "                   
                                                                          
            The phrase "handwave" seems to come                           
            up in these discussions quite often.                          
                                                                          
                                                                          
            A phrase I picked up from                                     
            someone at slashdot: dismissing                               
            the possibility of artificial      Though really, that just works
            intelligence with a "handwave      against the algorithmic    
            to Goedel".                        understanding style of AI, not
                                               the microcosmic god variety
                                               that's conquering the world.
                                                                          
                                                                          
                                                                          
                                                                          
One explanation of the the implications for this:                         
                                                                          
https://www.prospectmagazine.co.uk/magazine/kurt-godel-and-the-romance-of-logic
                                                                                                                      ~/End/Thought/RAW-GOEDEL
                                                                          
    "'The First Incompleteness Theorem' states the                        
    following. Given any consistent axiomatic system of                   
    arithmetic, there will be at least one statement about                
    numbers which cannot be proven in that system, and                    
    neither can its negation. Moreover (though this is not                
    actually part of the theorem, but of Goedel's                         
    reflections upon it), that statement has to be                        
    true. In other words, the Russell-Whitehead project                   
    was doomed, and so too were the hopes of anyone else                  
    who wanted to derive the whole of arithmetic from a                   
    system of logic. There is, and can be, no such thing                  
    as a consistent and complete axiomatisation of                        
    arithmetic. Moreover, that there cannot be such a                     
    system is itself a truth that can be inferred from a                  
    theorem of mathematical logic."                                       
                                                                          
       Now, the question arises: couldn't you take the                    
       one thing that can't be proved, and call it an                     
       additional axiom?  Actually, this does you no                      
       good, because there will always be another point                   
       like it, another truth you'd like to have                          
       established on your foundations that can't be...                   
                                                                          
                                                                          
   It could be it's a silly idea, but the wonky thought                   
   occurs to me that it might be the trouble is the idea                  
   that you need to have a fixed, finite number of known                  
   "postulates":                                                          
                                                                          
   What if you had an automatically self-extensible                       
   set of "axioms"?  One of your assumptions could be                     
   that anything which is not provable shall be                           
   assumed to be true... or false?                                        
                                                                              
      It could be the system would need to                                    
      bifurcate to follow both branches,             It's difficult to get    
      in one the proposition is assumed true         away from the need       
      in the other, false.                           for *additional* uses    
                                                     of human intuition to    
                                                     make sense of things     
                                                     like this.           


                                                               
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