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Theorem hbsbd 1982
Description: Deduction version of hbsb 1949. (Contributed by NM, 15-Feb-2013.) (Proof rewritten by Jim Kingdon, 23-Mar-2018.)
Hypotheses
Ref Expression
hbsbd.1 (𝜑 → ∀𝑥𝜑)
hbsbd.2 (𝜑 → ∀𝑧𝜑)
hbsbd.3 (𝜑 → (𝜓 → ∀𝑧𝜓))
Assertion
Ref Expression
hbsbd (𝜑 → ([𝑦 / 𝑥]𝜓 → ∀𝑧[𝑦 / 𝑥]𝜓))
Distinct variable group:   𝑦,𝑧
Allowed substitution hints:   𝜑(𝑥,𝑦,𝑧)   𝜓(𝑥,𝑦,𝑧)

Proof of Theorem hbsbd
StepHypRef Expression
1 hbsbd.2 . . . 4 (𝜑 → ∀𝑧𝜑)
21nfi 1462 . . 3 𝑧𝜑
3 hbsbd.3 . . . . . . 7 (𝜑 → (𝜓 → ∀𝑧𝜓))
41, 3nfdh 1524 . . . . . 6 (𝜑 → Ⅎ𝑧𝜓)
52, 4nfim1 1571 . . . . 5 𝑧(𝜑𝜓)
65nfsb 1946 . . . 4 𝑧[𝑦 / 𝑥](𝜑𝜓)
7 hbsbd.1 . . . . . 6 (𝜑 → ∀𝑥𝜑)
87sbrim 1956 . . . . 5 ([𝑦 / 𝑥](𝜑𝜓) ↔ (𝜑 → [𝑦 / 𝑥]𝜓))
98nfbii 1473 . . . 4 (Ⅎ𝑧[𝑦 / 𝑥](𝜑𝜓) ↔ Ⅎ𝑧(𝜑 → [𝑦 / 𝑥]𝜓))
106, 9mpbi 145 . . 3 𝑧(𝜑 → [𝑦 / 𝑥]𝜓)
112, 10nfrimi 1525 . 2 (𝜑 → Ⅎ𝑧[𝑦 / 𝑥]𝜓)
1211nfrd 1520 1 (𝜑 → ([𝑦 / 𝑥]𝜓 → ∀𝑧[𝑦 / 𝑥]𝜓))
Colors of variables: wff set class
Syntax hints:  wi 4  wal 1351  wnf 1460  [wsb 1762
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-io 709  ax-5 1447  ax-7 1448  ax-gen 1449  ax-ie1 1493  ax-ie2 1494  ax-8 1504  ax-10 1505  ax-11 1506  ax-i12 1507  ax-bndl 1509  ax-4 1510  ax-17 1526  ax-i9 1530  ax-ial 1534  ax-i5r 1535
This theorem depends on definitions:  df-bi 117  df-nf 1461  df-sb 1763
This theorem is referenced by: (None)
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