• What is natural number, exactly?

    From wij@wyniijj5@gmail.com to comp.theory on Mon Sep 15 08:23:08 2025
    From Newsgroup: comp.theory

    Procedural description is better than average formal axiomatic system:
    1. The abstract terms/symbols in average formal axiomatic system are often not
    used properly because they are so called 'abstract math. concept', not much
    one can deduce anything objectively from it, and so often are practically
    worse than in plain natural language.
    2. Average (current) formal system cannot describe procedural fact.
    Peano Theorem could be described in C language as:
    NaturnalNumber N[]={0}; // assuming N is a dynamic array
    NaturnalNumber next_natural_number(NaturnalNumber n) {
    return mak_next(N,m); // make a next natural number of m from N
    }
    bool is_natural_num(n) {
    if(is_format_correct(n)==false) { return false; }
    if(contain(N,n)) return true;
    N m= get_max(N);
    for(;;) {
    m=mak_next(N,m);
    insert(N,m); // insert m to N
    if(n==m) return true;
    }
    return false; // unreachable
    }
    So, in the procedural view above, natural number is essentially just a specification of the format of the symbol called number, and we can use next_natural_number(..). And, 'symbol' in procedural language implicitly suggests that it is finitely long (so, we cannot call is_natural_num(..)). While with the natural number defined by Peano Axiom, formally proving ∞∉ℕ is
    difficult, if not impossible... all the way down to infinity and other math.
    In math., 'natural number' is an abstract concept. In reasoning, errors can easily arise when abstract arguments in natural language involve two sets of natural numbers (intentionally or unintentionally). For example, if a "other natural number" set N is defined as "even numbers" {0, 2, 4, 8,...}, then the numbers 2 and 8 in N are not even numbers as defined by N. Reasoning of comparison can lead to confusion about the meaning of "even numbers." These errors are less likely to occur if expressed in a program (or with improved notation, such as N<0,+1>). The "natural numbers" commonly used in math. induction are often from a different natural numbers system.
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  • From wij@wyniijj5@gmail.com to comp.theory on Mon Sep 15 10:06:35 2025
    From Newsgroup: comp.theory

    On Mon, 2025-09-15 at 08:23 +0800, wij wrote:
    Procedural description is better than average formal axiomatic system:

     1. The abstract terms/symbols in average formal axiomatic system are often not
        used properly because they are so called 'abstract math. concept', not much
        one can deduce anything objectively from it, and so often are practically
        worse than in plain natural language.

     2. Average (current) formal system cannot describe procedural fact.

    Peano Theorem could be described in C language as:

      NaturnalNumber N[]={0};   // assuming N is a dynamic array

      NaturnalNumber next_natural_number(NaturnalNumber n) {
       return mak_next(N,m);    // make a next natural number of m from N
      }

      bool is_natural_num(n) {
       if(is_format_correct(n)==false) { return false; }
       if(contain(N,n)) return true;
       N m= get_max(N);
       for(;;) {
         m=mak_next(N,m);   
         insert(N,m);        // insert m to N
         if(n==m) return true;
       }
       return false; // unreachable
      }

    So, in the procedural view above, natural number is essentially just a specification of the format of the symbol called number, and we can use next_natural_number(..). And, 'symbol' in procedural language implicitly suggests that it is finitely long (so, we cannot call is_natural_num(..)). While with the natural number defined by Peano Axiom, formally proving ∞∉ℕ is
    difficult, if not impossible... all the way down to infinity and other math.

    In math., 'natural number' is an abstract concept. In reasoning, errors can easily arise when abstract arguments in natural language involve two sets of natural numbers (intentionally or unintentionally). For example, if a "other  
    natural number" set N is defined as "even numbers" {0, 2, 4, 8,...}, then the
    numbers 2 and 8 in N are not even numbers as defined by N. Reasoning of comparison can lead to confusion about the meaning of "even numbers." These errors are less likely to occur if expressed in a program (or with improved notation, such as N<0,+1>). The "natural numbers" commonly used in math. induction are often from a different natural numbers system.
    From about, we can easily define real number as such:
    EN::= Same as the natural numbers defined above, but the number (symbol) can
    be infinitely long.
    ℝ::= {x| x=p/q or -p/q, p,q∈EN, q≠0}
    Note that real number is but an extension of rational number that includes infinitely long symbols (no way to explicitly appear).
    There are lots of different theories (either inconsistent or not closed) about what real number is. A simple,intuitive one is handy to have and we actually  already knew it naturally. Why bother The Emperor's New Clothes?
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  • From Chris M. Thomasson@chris.m.thomasson.1@gmail.com to comp.theory on Sun Sep 14 20:38:40 2025
    From Newsgroup: comp.theory

    On 9/14/2025 5:23 PM, wij wrote:
    Procedural description is better than average formal axiomatic system:
    [...]

    Zero aside for a moment, but a tree might be a fairly decent start? A
    two ary tree:


    0
    / \
    / \
    / \
    1 2
    / \ / \
    / \ / \
    3 4 5 6
    ..........................

    on and on... Three ary would be:


    0
    /|\
    / | \
    / | \
    1 2 3
    ........................

    on and on...


    The tree levels and their numbers already have their inherent properties
    in them? the root node is zero.





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