A method for proving something about all sets in ZFC

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The discussion centers on a document proposing a method to generalize induction in natural numbers to prove statements about all sets in ZFC set theory through "grammatical systems." Feedback highlights that while the concepts may be familiar, the terminology used is unconventional and contains inaccuracies, particularly regarding the definitions of grammatical systems for sets versus classes. The author acknowledges a lack of familiarity with existing literature and expresses a desire to explore other presentations of the result, considering whether a different foundational framework like NFU might be necessary. Participants suggest reviewing Hinman's "Fundamentals of Logic" for clarity and accuracy. Overall, the conversation emphasizes the need for careful definition and understanding of terms within set theory.
phoenixthoth
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I would appreciate any and all feedback regarding this document currently housed in Google docs. Basically, I generalize induction among natural numbers to an extreme in an environment regarding what I call grammatical systems. Then an induction principle is derived from that which holds in ZFC set theory (and perhaps other set theories) which would enable someone to prove statements about all sets in ZFC.

https://docs.google.com/document/d/1amDb4Yti4egpKfcO2oLcnGAH8UpC8_tKb7ivuH3AT7A/edit?usp=sharing
 
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So what kind of feedback do you want? Everything in the document is rather well-known, it's only phrased in terms that are pretty weird. There are some inaccurate things in the document though, so perhaps you want to discuss that?
 
In particular, take a look at section 1.2 of Hinman's "Fundamentals of logic". You should be more careful in your document however since you only define "grammatical systems" for sets, while you later use them for classes when dealing with ZF.
 
micromass said:
So what kind of feedback do you want? Everything in the document is rather well-known, it's only phrased in terms that are pretty weird. There are some inaccurate things in the document though, so perhaps you want to discuss that?
That in itself is very useful feedback. Thank you. I guess I haven't studied enough set theory because I haven't seen this result before. I'm glad I don't have to reinvent the wheel. I will see if I can find Hinman. We might as well discuss those innacurate things. I don't know if changing the terms I use from sets to classes when defining grammatical systems would harm anything. I was also thinking, alternatively, that maybe I should note that I must not be working within ZFC in order to prove something about ZFC; I apparently need something else like NFU or something that isn't ZFC. I'm excited to go find out other presentations of this result which I was suspecting was well-known, in part to see if more or less machinery is required in other presentations.
 
Are there any references online that explain this result differently from how I did it (or almost did it) as I cannot find Hinman's book online?
 
I was reading documentation about the soundness and completeness of logic formal systems. Consider the following $$\vdash_S \phi$$ where ##S## is the proof-system making part the formal system and ##\phi## is a wff (well formed formula) of the formal language. Note the blank on left of the turnstile symbol ##\vdash_S##, as far as I can tell it actually represents the empty set. So what does it mean ? I guess it actually means ##\phi## is a theorem of the formal system, i.e. there is a...
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