Theorem eldisjs6 39539

Description: Elementhood in the class of disjoints. A relation 𝑅 is in Disjs iff:

it is relation-typed, and

its quotient-map QMap 𝑅 is itself disjoint, and

its quotient-carrier ran QMap 𝑅 = (dom 𝑅 / 𝑅) lies in ElDisjs (element-disjoint carriers).

This is the central "stability-by-decomposition" theorem for Disjs: it explains why Disjs is internally well-behaved without adding an external stability clause. It is the exact template that PetParts imitates: for pet 39564, the analogue of "map layer" is the disjointness of the lifted span, the analogue of "carrier layer" is the block-lift fixpoint (BlockLiftFix), and then adds external grade stability (SucMap ShiftStable) which Disjs does not need. (Contributed by Peter Mazsa, 16-Feb-2026.)

Assertion

Ref	Expression
eldisjs6	⊢ (𝑅 ∈ Disjs ↔ (𝑅 ∈ Rels ∧ (ran QMap 𝑅 ∈ ElDisjs ∧ QMap 𝑅 ∈ Disjs )))

Proof of Theorem eldisjs6

Dummy variables 𝑢 𝑣 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		eldisjsim2 39534	. . 3 ⊢ (𝑅 ∈ Disjs → 𝑅 ∈ Rels )
2		eldisjsim4 39537	. . 3 ⊢ (𝑅 ∈ Disjs → ran QMap 𝑅 ∈ ElDisjs )
3		eldisjsim5 39538	. . 3 ⊢ (𝑅 ∈ Disjs → QMap 𝑅 ∈ Disjs )
4	1, 2, 3	jca32 524	. 2 ⊢ (𝑅 ∈ Disjs → (𝑅 ∈ Rels ∧ (ran QMap 𝑅 ∈ ElDisjs ∧ QMap 𝑅 ∈ Disjs )))
5		rnqmapeleldisjsim 39461	. . . . . . 7 ⊢ ((𝑅 ∈ Rels ∧ ran QMap 𝑅 ∈ ElDisjs ∧ (𝑢 ∈ dom 𝑅 ∧ 𝑣 ∈ dom 𝑅)) → (([𝑢]𝑅 ∩ [𝑣]𝑅) ≠ ∅ → [𝑢]𝑅 = [𝑣]𝑅))
6	5	3adant2r 1196	. . . . . 6 ⊢ ((𝑅 ∈ Rels ∧ (ran QMap 𝑅 ∈ ElDisjs ∧ QMap 𝑅 ∈ Disjs ) ∧ (𝑢 ∈ dom 𝑅 ∧ 𝑣 ∈ dom 𝑅)) → (([𝑢]𝑅 ∩ [𝑣]𝑅) ≠ ∅ → [𝑢]𝑅 = [𝑣]𝑅))
7		qmapeldisjsim 39459	. . . . . . 7 ⊢ ((𝑅 ∈ Rels ∧ QMap 𝑅 ∈ Disjs ∧ (𝑢 ∈ dom 𝑅 ∧ 𝑣 ∈ dom 𝑅)) → ([𝑢]𝑅 = [𝑣]𝑅 → 𝑢 = 𝑣))
8	7	3adant2l 1195	. . . . . 6 ⊢ ((𝑅 ∈ Rels ∧ (ran QMap 𝑅 ∈ ElDisjs ∧ QMap 𝑅 ∈ Disjs ) ∧ (𝑢 ∈ dom 𝑅 ∧ 𝑣 ∈ dom 𝑅)) → ([𝑢]𝑅 = [𝑣]𝑅 → 𝑢 = 𝑣))
9	6, 8	syld 48	. . . . 5 ⊢ ((𝑅 ∈ Rels ∧ (ran QMap 𝑅 ∈ ElDisjs ∧ QMap 𝑅 ∈ Disjs ) ∧ (𝑢 ∈ dom 𝑅 ∧ 𝑣 ∈ dom 𝑅)) → (([𝑢]𝑅 ∩ [𝑣]𝑅) ≠ ∅ → 𝑢 = 𝑣))
10	9	3expia 1137	. . . 4 ⊢ ((𝑅 ∈ Rels ∧ (ran QMap 𝑅 ∈ ElDisjs ∧ QMap 𝑅 ∈ Disjs )) → ((𝑢 ∈ dom 𝑅 ∧ 𝑣 ∈ dom 𝑅) → (([𝑢]𝑅 ∩ [𝑣]𝑅) ≠ ∅ → 𝑢 = 𝑣)))
11	10	ralrimivv 3213	. . 3 ⊢ ((𝑅 ∈ Rels ∧ (ran QMap 𝑅 ∈ ElDisjs ∧ QMap 𝑅 ∈ Disjs )) → ∀𝑢 ∈ dom 𝑅∀𝑣 ∈ dom 𝑅(([𝑢]𝑅 ∩ [𝑣]𝑅) ≠ ∅ → 𝑢 = 𝑣))
12		elrelsrelim 39042	. . . . . 6 ⊢ (𝑅 ∈ Rels → Rel 𝑅)
13		dfdisjALTV5a 39402	. . . . . . 7 ⊢ ( Disj 𝑅 ↔ (∀𝑢 ∈ dom 𝑅∀𝑣 ∈ dom 𝑅(([𝑢]𝑅 ∩ [𝑣]𝑅) ≠ ∅ → 𝑢 = 𝑣) ∧ Rel 𝑅))
14	13	simplbi2com 507	. . . . . 6 ⊢ (Rel 𝑅 → (∀𝑢 ∈ dom 𝑅∀𝑣 ∈ dom 𝑅(([𝑢]𝑅 ∩ [𝑣]𝑅) ≠ ∅ → 𝑢 = 𝑣) → Disj 𝑅))
15	12, 14	syl 18	. . . . 5 ⊢ (𝑅 ∈ Rels → (∀𝑢 ∈ dom 𝑅∀𝑣 ∈ dom 𝑅(([𝑢]𝑅 ∩ [𝑣]𝑅) ≠ ∅ → 𝑢 = 𝑣) → Disj 𝑅))
16		eldisjsdisj 39423	. . . . 5 ⊢ (𝑅 ∈ Rels → (𝑅 ∈ Disjs ↔ Disj 𝑅))
17	15, 16	sylibrd 262	. . . 4 ⊢ (𝑅 ∈ Rels → (∀𝑢 ∈ dom 𝑅∀𝑣 ∈ dom 𝑅(([𝑢]𝑅 ∩ [𝑣]𝑅) ≠ ∅ → 𝑢 = 𝑣) → 𝑅 ∈ Disjs ))
18	17	adantr 485	. . 3 ⊢ ((𝑅 ∈ Rels ∧ (ran QMap 𝑅 ∈ ElDisjs ∧ QMap 𝑅 ∈ Disjs )) → (∀𝑢 ∈ dom 𝑅∀𝑣 ∈ dom 𝑅(([𝑢]𝑅 ∩ [𝑣]𝑅) ≠ ∅ → 𝑢 = 𝑣) → 𝑅 ∈ Disjs ))
19	11, 18	mpd 16	. 2 ⊢ ((𝑅 ∈ Rels ∧ (ran QMap 𝑅 ∈ ElDisjs ∧ QMap 𝑅 ∈ Disjs )) → 𝑅 ∈ Disjs )
20	4, 19	impbii 212	1 ⊢ (𝑅 ∈ Disjs ↔ (𝑅 ∈ Rels ∧ (ran QMap 𝑅 ∈ ElDisjs ∧ QMap 𝑅 ∈ Disjs )))

Syntax hints:   → wi 4   ↔ wb 209   ∧ wa 400   ∧ w3a 1101   = wceq 1568   ∈ wcel 2150   ≠ wne 2965  ∀wral 3086   ∩ cin 3912  ∅c0 4294  dom cdm 5665  ran crn 5666  Rel wrel 5670  [cec 8695   QMap cqmap 38774   Rels crels 38784   Disjs cdisjs 38817   Disj wdisjALTV 38818   ElDisjs celdisjs 38819

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1823  ax-4 1837  ax-5 1938  ax-6 1995  ax-7 2036  ax-8 2152  ax-9 2160  ax-10 2183  ax-11 2199  ax-12 2220  ax-ext 2742  ax-rep 5243  ax-sep 5262  ax-nul 5274  ax-pow 5340  ax-pr 5408  ax-un 7736

This theorem depends on definitions:  df-bi 210  df-an 401  df-or 861  df-3an 1103  df-tru 1571  df-fal 1581  df-ex 1808  df-nf 1812  df-sb 2099  df-mo 2574  df-eu 2604  df-clab 2749  df-cleq 2762  df-clel 2845  df-nfc 2919  df-ne 2966  df-ral 3087  df-rex 3097  df-rmo 3376  df-reu 3377  df-rab 3424  df-v 3464  df-sbc 3753  df-csb 3862  df-dif 3916  df-un 3918  df-in 3920  df-ss 3930  df-nul 4295  df-if 4493  df-pw 4569  df-sn 4595  df-pr 4597  df-op 4601  df-uni 4878  df-iun 4963  df-br 5115  df-opab 5179  df-mpt 5198  df-id 5560  df-eprel 5565  df-xp 5671  df-rel 5672  df-cnv 5673  df-co 5674  df-dm 5675  df-rn 5676  df-res 5677  df-ima 5678  df-iota 6496  df-fun 6542  df-fn 6543  df-f 6544  df-f1 6545  df-fo 6546  df-f1o 6547  df-fv 6548  df-ec 8699  df-qs 8703  df-rels 39039  df-qmap 39045  df-coss 39100  df-ssr 39177  df-refrel 39191  df-cnvrefs 39204  df-cnvrefrels 39205  df-cnvrefrel 39206  df-symrel 39223  df-trrel 39257  df-eqvrel 39268  df-funALTV 39366  df-disjss 39387  df-disjs 39388  df-disjALTV 39389  df-eldisjs 39390  df-eldisj 39391

This theorem is referenced by:  eldisjs7  39540  dfdisjs6  39541