Theorem clsslem 13769

Description: The closure of a subclass is a subclass of the closure. (Contributed by RP, 16-May-2020.)

Assertion

Ref	Expression
clsslem	⊢ (𝑅 ⊆ 𝑆 → ∩ {𝑟 ∣ (𝑅 ⊆ 𝑟 ∧ 𝜑)} ⊆ ∩ {𝑟 ∣ (𝑆 ⊆ 𝑟 ∧ 𝜑)})

Distinct variable groups:   𝑅,𝑟   𝑆,𝑟

Allowed substitution hint:   𝜑(𝑟)

Proof of Theorem clsslem

Step	Hyp	Ref	Expression
1		sstr2 3643	. . . 4 ⊢ (𝑅 ⊆ 𝑆 → (𝑆 ⊆ 𝑟 → 𝑅 ⊆ 𝑟))
2	1	anim1d 587	. . 3 ⊢ (𝑅 ⊆ 𝑆 → ((𝑆 ⊆ 𝑟 ∧ 𝜑) → (𝑅 ⊆ 𝑟 ∧ 𝜑)))
3	2	ss2abdv 3708	. 2 ⊢ (𝑅 ⊆ 𝑆 → {𝑟 ∣ (𝑆 ⊆ 𝑟 ∧ 𝜑)} ⊆ {𝑟 ∣ (𝑅 ⊆ 𝑟 ∧ 𝜑)})
4		intss 4530	. 2 ⊢ ({𝑟 ∣ (𝑆 ⊆ 𝑟 ∧ 𝜑)} ⊆ {𝑟 ∣ (𝑅 ⊆ 𝑟 ∧ 𝜑)} → ∩ {𝑟 ∣ (𝑅 ⊆ 𝑟 ∧ 𝜑)} ⊆ ∩ {𝑟 ∣ (𝑆 ⊆ 𝑟 ∧ 𝜑)})
5	3, 4	syl 17	1 ⊢ (𝑅 ⊆ 𝑆 → ∩ {𝑟 ∣ (𝑅 ⊆ 𝑟 ∧ 𝜑)} ⊆ ∩ {𝑟 ∣ (𝑆 ⊆ 𝑟 ∧ 𝜑)})

Syntax hints:   → wi 4   ∧ wa 383  {cab 2637   ⊆ wss 3607  ∩ cint 4507

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1762  ax-4 1777  ax-5 1879  ax-6 1945  ax-7 1981  ax-9 2039  ax-10 2059  ax-11 2074  ax-12 2087  ax-13 2282  ax-ext 2631

This theorem depends on definitions:  df-bi 197  df-or 384  df-an 385  df-tru 1526  df-ex 1745  df-nf 1750  df-sb 1938  df-clab 2638  df-cleq 2644  df-clel 2647  df-nfc 2782  df-ral 2946  df-in 3614  df-ss 3621  df-int 4508

This theorem is referenced by:  trclsslem  13775