Detailed syntax breakdown of Axiom ax-hvass
| Step | Hyp | Ref
| Expression |
| 1 | | cA |
. . . 4
class A |
| 2 | | chil 4958 |
. . . 4
class ℋ |
| 3 | 1, 2 | wcel 1092 |
. . 3
wff A ∈
ℋ |
| 4 | | cB |
. . . 4
class B |
| 5 | 4, 2 | wcel 1092 |
. . 3
wff B ∈
ℋ |
| 6 | | cC |
. . . 4
class C |
| 7 | 6, 2 | wcel 1092 |
. . 3
wff C ∈
ℋ |
| 8 | 3, 5, 7 | w3a 581 |
. 2
wff (A ∈
ℋ ∧ B ∈ ℋ ∧
C ∈ ℋ ) |
| 9 | | cva 4959 |
. . . . 5
class +v |
| 10 | 1, 4, 9 | co 3001 |
. . . 4
class (A
+v B) |
| 11 | 10, 6, 9 | co 3001 |
. . 3
class ((A
+v B)
+v C) |
| 12 | 4, 6, 9 | co 3001 |
. . . 4
class (B
+v C) |
| 13 | 1, 12, 9 | co 3001 |
. . 3
class (A
+v (B
+v C)) |
| 14 | 11, 13 | wceq 1091 |
. 2
wff ((A
+v B)
+v C) = (A +v (B +v C)) |
| 15 | 8, 14 | wi 2 |
1
wff ((A ∈
ℋ ∧ B ∈ ℋ ∧
C ∈ ℋ ) → ((A +v B) +v C) = (A
+v (B
+v C))) |