Theorem eldisjs6 39617

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 39642, 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 39612	. . 3 ⊢ (𝑅 ∈ Disjs → 𝑅 ∈ Rels )
2		eldisjsim4 39615	. . 3 ⊢ (𝑅 ∈ Disjs → ran QMap 𝑅 ∈ ElDisjs )
3		eldisjsim5 39616	. . 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 39539	. . . . . . 7 ⊢ ((𝑅 ∈ Rels ∧ ran QMap 𝑅 ∈ ElDisjs ∧ (𝑢 ∈ dom 𝑅 ∧ 𝑣 ∈ dom 𝑅)) → (([𝑢]𝑅 ∩ [𝑣]𝑅) ≠ ∅ → [𝑢]𝑅 = [𝑣]𝑅))
6	5	3adant2r 1197	. . . . . 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 39537	. . . . . . 7 ⊢ ((𝑅 ∈ Rels ∧ QMap 𝑅 ∈ Disjs ∧ (𝑢 ∈ dom 𝑅 ∧ 𝑣 ∈ dom 𝑅)) → ([𝑢]𝑅 = [𝑣]𝑅 → 𝑢 = 𝑣))
8	7	3adant2l 1196	. . . . . 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 1138	. . . 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 3205	. . 3 ⊢ ((𝑅 ∈ Rels ∧ (ran QMap 𝑅 ∈ ElDisjs ∧ QMap 𝑅 ∈ Disjs )) → ∀𝑢 ∈ dom 𝑅∀𝑣 ∈ dom 𝑅(([𝑢]𝑅 ∩ [𝑣]𝑅) ≠ ∅ → 𝑢 = 𝑣))
12		elrelsrelim 39120	. . . . . 6 ⊢ (𝑅 ∈ Rels → Rel 𝑅)
13		dfdisjALTV5a 39480	. . . . . . 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 39501	. . . . 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 )))

This proof depends on syntax axioms:   → wi 4   ↔ wb 209   ∧ wa 400   ∧ w3a 1102   = wceq 1569   ∈ wcel 2142   ≠ wne 2957  ∀wral 3078   ∩ cin 3903  ∅c0 4285  dom cdm 5660  ran crn 5661  Rel wrel 5665  [cec 8690   QMap cqmap 38852   Rels crels 38862   Disjs cdisjs 38895   Disj wdisjALTV 38896   ElDisjs celdisjs 38897

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1824  ax-4 1838  ax-5 1939  ax-6 1996  ax-7 2037  ax-8 2144  ax-9 2152  ax-10 2175  ax-11 2191  ax-12 2212  ax-ext 2734  ax-rep 5237  ax-sep 5256  ax-nul 5268  ax-pow 5335  ax-pr 5403  ax-un 7734

This proof depends on definitions:  df-bi 210  df-an 401  df-or 861  df-3an 1104  df-tru 1572  df-fal 1582  df-ex 1809  df-nf 1813  df-sb 2096  df-mo 2566  df-eu 2596  df-clab 2741  df-cleq 2754  df-clel 2837  df-nfc 2911  df-ne 2958  df-ral 3079  df-rex 3089  df-rmo 3368  df-reu 3369  df-rab 3416  df-v 3456  df-sbc 3744  df-csb 3853  df-dif 3907  df-un 3909  df-in 3911  df-ss 3921  df-nul 4286  df-if 4487  df-pw 4563  df-sn 4589  df-pr 4591  df-op 4595  df-uni 4872  df-iun 4957  df-br 5109  df-opab 5173  df-mpt 5192  df-id 5555  df-eprel 5560  df-xp 5666  df-rel 5667  df-cnv 5668  df-co 5669  df-dm 5670  df-rn 5671  df-res 5672  df-ima 5673  df-iota 6492  df-fun 6538  df-fn 6539  df-f 6540  df-f1 6541  df-fo 6542  df-f1o 6543  df-fv 6544  df-ec 8694  df-qs 8698  df-rels 39117  df-qmap 39123  df-coss 39178  df-ssr 39255  df-refrel 39269  df-cnvrefs 39282  df-cnvrefrels 39283  df-cnvrefrel 39284  df-symrel 39301  df-trrel 39335  df-eqvrel 39346  df-funALTV 39444  df-disjss 39465  df-disjs 39466  df-disjALTV 39467  df-eldisjs 39468  df-eldisj 39469

This theorem is used by:  eldisjs7  39618  dfdisjs6  39619