Re: A new Arithmetic Principle?



Jim Spriggs wrote:

Nam Nguyen wrote:

Consider the following (proposed) Arithmetic Principle,
say, "Anti-Induction" [or just "AI"]:

(1) There _exists_ an arithmetic number that we don't know
    if it's even. [I.e. no formalization can assert that it's even]

or a more generalized version, named "gAI" which is:

(2) If P is an arithmetic property that:

    a) if P is true for an arithmetic number n0
    b) if P(nk) is true for an nk >= n0, then there
       exist an nk' >= n0 and nk'' >= n0 such that
       P(nk') is true and P(nk'') is false.

Basically gAI would state that certain arithmetic knowledge is not
"inductive".

Could/should we adopt gAI?


In the presence of what other axioms?

Not "axioms", imho. Given that Arithemtic is used for the foundation/framework of, say FOL, then the question would be about what kind of impact to the overal FOL based mathematics.



If we do, what would be the possible
consequences?

---Nam Nguyen
.