Metamath Proof Explorer


Theorem frege132

Description: Lemma for frege133 . Proposition 132 of Frege1879 p. 86. (Contributed by RP, 9-Jul-2020) (Proof modification is discouraged.)

Ref Expression
Hypotheses frege130.m ⊢ M ∈ U
frege130.r ⊢ R ∈ V
Assertion frege132 ⊢ R hereditary t+ ⁡ R -1 M ∪ t+ ⁡ R ∪ I M → X t+ ⁡ R M → X t+ ⁡ R Y → ¬ Y t+ ⁡ R M → M t+ ⁡ R ∪ I Y → Fun ⁡ R -1 -1 → X t+ ⁡ R M → X t+ ⁡ R Y → ¬ Y t+ ⁡ R M → M t+ ⁡ R ∪ I Y

Proof

Step Hyp Ref Expression
1 frege130.m ⊢ M ∈ U
2 frege130.r ⊢ R ∈ V
3 1 2 frege131 ⊢ Fun ⁡ R -1 -1 → R hereditary t+ ⁡ R -1 M ∪ t+ ⁡ R ∪ I M
4 frege9 ⊢ Fun ⁡ R -1 -1 → R hereditary t+ ⁡ R -1 M ∪ t+ ⁡ R ∪ I M → R hereditary t+ ⁡ R -1 M ∪ t+ ⁡ R ∪ I M → X t+ ⁡ R M → X t+ ⁡ R Y → ¬ Y t+ ⁡ R M → M t+ ⁡ R ∪ I Y → Fun ⁡ R -1 -1 → X t+ ⁡ R M → X t+ ⁡ R Y → ¬ Y t+ ⁡ R M → M t+ ⁡ R ∪ I Y
5 3 4 ax-mp ⊢ R hereditary t+ ⁡ R -1 M ∪ t+ ⁡ R ∪ I M → X t+ ⁡ R M → X t+ ⁡ R Y → ¬ Y t+ ⁡ R M → M t+ ⁡ R ∪ I Y → Fun ⁡ R -1 -1 → X t+ ⁡ R M → X t+ ⁡ R Y → ¬ Y t+ ⁡ R M → M t+ ⁡ R ∪ I Y