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Mirrors > Home > NFE Home > Th. List > albidh | GIF version |
Description: Formula-building rule for universal quantifier (deduction rule). (Contributed by NM, 5-Aug-1993.) |
Ref | Expression |
---|---|
albidh.1 | ⊢ (φ → ∀xφ) |
albidh.2 | ⊢ (φ → (ψ ↔ χ)) |
Ref | Expression |
---|---|
albidh | ⊢ (φ → (∀xψ ↔ ∀xχ)) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | albidh.1 | . . 3 ⊢ (φ → ∀xφ) | |
2 | albidh.2 | . . 3 ⊢ (φ → (ψ ↔ χ)) | |
3 | 1, 2 | alrimih 1565 | . 2 ⊢ (φ → ∀x(ψ ↔ χ)) |
4 | albi 1564 | . 2 ⊢ (∀x(ψ ↔ χ) → (∀xψ ↔ ∀xχ)) | |
5 | 3, 4 | syl 15 | 1 ⊢ (φ → (∀xψ ↔ ∀xχ)) |
Colors of variables: wff setvar class |
Syntax hints: → wi 4 ↔ wb 176 ∀wal 1540 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1546 ax-5 1557 |
This theorem depends on definitions: df-bi 177 |
This theorem is referenced by: albidv 1625 albid 1772 ax10lem4 1941 ax9 1949 dral2 1966 dral2-o 2181 ax11indalem 2197 ax11inda2ALT 2198 ax11inda 2200 |
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