Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Strong Completeness of Normal Modal Logic #15

Merged
merged 24 commits into from
Jan 29, 2024

Conversation

SnO2WMaN
Copy link
Collaborator

@SnO2WMaN SnO2WMaN commented Jan 21, 2024

TODO

  • Lindenbaum補題
  • completeness_def
  • Truth Lemma
  • 各々の公理図式とカノニカルモデルの性質の対応関係
  • 演繹定理

@SnO2WMaN SnO2WMaN marked this pull request as ready for review January 25, 2024 11:13
@SnO2WMaN
Copy link
Collaborator Author

レビュー終わり次第マージ可能です.

Copy link
Owner

@iehality iehality left a comment

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

レビューしたと思ったが公開されていなかった。申し訳ない。

@@ -3,99 +3,183 @@ import Logic.Logic.Calculus

namespace LO

class Deduction {F : Type u} [LogicSymbol F] (Bew : Set F → F → Sort*) where
axm : ∀ {f}, f ∈ T → Bew T f
class Deduction {F : Type u} [LogicSymbol F] (Bew : Finset F → F → Sort*) where
Copy link
Owner

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

公理をFinsetではなく集合にしたほうが良いと思う(普通の導出関係を考えるならば同等のはずで、それならばより一般的な集合のほうが良いと思う)

Copy link
Collaborator Author

@SnO2WMaN SnO2WMaN Jan 29, 2024

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Hilbert流で最初からSetを許容すると,例えば演繹定理で $\Gamma \vdash \varphi$$\Gamma$ を全て $\land, \lor$ で繋いで右側に寄せる操作を考えたときに無限の長さの論理式が出来たりして困る気がするのですが,どうなのでしょうか.(今後必要になる操作なのかはまだ不明ですが)

Copy link
Owner

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

それはおそらく次の補題を用いれば問題ないと思う.
証明で使用する公理は有限個なので帰納法で以下に相当する補題が証明できるはず

def Deduction.compact : T ⊢ p → (t : { t : Finset F // t ⊆ T }) × (t ⊢ p)

Copy link
Collaborator Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

修正しました.

@iehality iehality merged commit 678d966 into iehality:master Jan 29, 2024
1 check passed
@SnO2WMaN SnO2WMaN deleted the completeness branch January 29, 2024 18:21
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
None yet
Projects
None yet
Development

Successfully merging this pull request may close these issues.

None yet

2 participants