Theorem cardsdomel 9891

Description: A cardinal strictly dominates its members. Equivalent to Proposition 10.37 of [TakeutiZaring] p. 93. (Contributed by Mario Carneiro, 15-Jan-2013.) (Revised by Mario Carneiro, 4-Jun-2015.)

Assertion

Ref	Expression
cardsdomel	⊢ ((𝐴 ∈ On ∧ 𝐵 ∈ dom card) → (𝐴 ≺ 𝐵 ↔ 𝐴 ∈ (card‘𝐵)))

Proof of Theorem cardsdomel

Step	Hyp	Ref	Expression
1		cardid2 9870	. . . . . . 7 ⊢ (𝐵 ∈ dom card → (card‘𝐵) ≈ 𝐵)
2	1	ensymd 8947	. . . . . 6 ⊢ (𝐵 ∈ dom card → 𝐵 ≈ (card‘𝐵))
3		sdomentr 9044	. . . . . 6 ⊢ ((𝐴 ≺ 𝐵 ∧ 𝐵 ≈ (card‘𝐵)) → 𝐴 ≺ (card‘𝐵))
4	2, 3	sylan2 594	. . . . 5 ⊢ ((𝐴 ≺ 𝐵 ∧ 𝐵 ∈ dom card) → 𝐴 ≺ (card‘𝐵))
5		ssdomg 8942	. . . . . . . 8 ⊢ (𝐴 ∈ On → ((card‘𝐵) ⊆ 𝐴 → (card‘𝐵) ≼ 𝐴))
6		cardon 9861	. . . . . . . . 9 ⊢ (card‘𝐵) ∈ On
7		domtriord 9056	. . . . . . . . 9 ⊢ (((card‘𝐵) ∈ On ∧ 𝐴 ∈ On) → ((card‘𝐵) ≼ 𝐴 ↔ ¬ 𝐴 ≺ (card‘𝐵)))
8	6, 7	mpan 691	. . . . . . . 8 ⊢ (𝐴 ∈ On → ((card‘𝐵) ≼ 𝐴 ↔ ¬ 𝐴 ≺ (card‘𝐵)))
9	5, 8	sylibd 239	. . . . . . 7 ⊢ (𝐴 ∈ On → ((card‘𝐵) ⊆ 𝐴 → ¬ 𝐴 ≺ (card‘𝐵)))
10	9	con2d 134	. . . . . 6 ⊢ (𝐴 ∈ On → (𝐴 ≺ (card‘𝐵) → ¬ (card‘𝐵) ⊆ 𝐴))
11		ontri1 6352	. . . . . . . 8 ⊢ (((card‘𝐵) ∈ On ∧ 𝐴 ∈ On) → ((card‘𝐵) ⊆ 𝐴 ↔ ¬ 𝐴 ∈ (card‘𝐵)))
12	6, 11	mpan 691	. . . . . . 7 ⊢ (𝐴 ∈ On → ((card‘𝐵) ⊆ 𝐴 ↔ ¬ 𝐴 ∈ (card‘𝐵)))
13	12	con2bid 354	. . . . . 6 ⊢ (𝐴 ∈ On → (𝐴 ∈ (card‘𝐵) ↔ ¬ (card‘𝐵) ⊆ 𝐴))
14	10, 13	sylibrd 259	. . . . 5 ⊢ (𝐴 ∈ On → (𝐴 ≺ (card‘𝐵) → 𝐴 ∈ (card‘𝐵)))
15	4, 14	syl5 34	. . . 4 ⊢ (𝐴 ∈ On → ((𝐴 ≺ 𝐵 ∧ 𝐵 ∈ dom card) → 𝐴 ∈ (card‘𝐵)))
16	15	expcomd 416	. . 3 ⊢ (𝐴 ∈ On → (𝐵 ∈ dom card → (𝐴 ≺ 𝐵 → 𝐴 ∈ (card‘𝐵))))
17	16	imp 406	. 2 ⊢ ((𝐴 ∈ On ∧ 𝐵 ∈ dom card) → (𝐴 ≺ 𝐵 → 𝐴 ∈ (card‘𝐵)))
18		cardsdomelir 9890	. 2 ⊢ (𝐴 ∈ (card‘𝐵) → 𝐴 ≺ 𝐵)
19	17, 18	impbid1 225	1 ⊢ ((𝐴 ∈ On ∧ 𝐵 ∈ dom card) → (𝐴 ≺ 𝐵 ↔ 𝐴 ∈ (card‘𝐵)))

Syntax hints:  ¬ wn 3   → wi 4   ↔ wb 206   ∧ wa 395   ∈ wcel 2114   ⊆ wss 3902   class class class wbr 5099  dom cdm 5625  Oncon0 6318  ‘cfv 6493   ≈ cen 8885   ≼ cdom 8886   ≺ csdm 8887  cardccrd 9852

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1797  ax-4 1811  ax-5 1912  ax-6 1969  ax-7 2010  ax-8 2116  ax-9 2124  ax-10 2147  ax-11 2163  ax-12 2185  ax-ext 2709  ax-sep 5242  ax-nul 5252  ax-pow 5311  ax-pr 5378  ax-un 7683

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 849  df-3or 1088  df-3an 1089  df-tru 1545  df-fal 1555  df-ex 1782  df-nf 1786  df-sb 2069  df-mo 2540  df-eu 2570  df-clab 2716  df-cleq 2729  df-clel 2812  df-nfc 2886  df-ne 2934  df-ral 3053  df-rex 3062  df-rab 3401  df-v 3443  df-dif 3905  df-un 3907  df-in 3909  df-ss 3919  df-pss 3922  df-nul 4287  df-if 4481  df-pw 4557  df-sn 4582  df-pr 4584  df-op 4588  df-uni 4865  df-int 4904  df-br 5100  df-opab 5162  df-mpt 5181  df-tr 5207  df-id 5520  df-eprel 5525  df-po 5533  df-so 5534  df-fr 5578  df-we 5580  df-xp 5631  df-rel 5632  df-cnv 5633  df-co 5634  df-dm 5635  df-rn 5636  df-res 5637  df-ima 5638  df-ord 6321  df-on 6322  df-iota 6449  df-fun 6495  df-fn 6496  df-f 6497  df-f1 6498  df-fo 6499  df-f1o 6500  df-fv 6501  df-er 8638  df-en 8889  df-dom 8890  df-sdom 8891  df-card 9856

This theorem is referenced by:  iscard  9892  cardval2  9908  infxpenlem  9928  alephnbtwn  9986  alephnbtwn2  9987  alephord2  9991  alephsdom  10001  pwsdompw  10118  inaprc  10752