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Theorem 0cat 10691
Description: Category 0. No object, no morphism.
Assertion
Ref Expression
0cat |- <.<.(/), (/)>., <.(/), (/)>.>. e. Cat

Proof of Theorem 0cat
StepHypRef Expression
1 0ex 2711 . . . 4 |- (/) e. V
21, 1, 13pm3.2i 818 . . 3 |- ((/) e. V /\ (/) e. V /\ (/) e. V)
3 eqid 1475 . . . 4 |- dom (/) = dom (/)
43, 3iscat 10687 . . 3 |- ((((/) e. V /\ (/) e. V /\ (/) e. V) /\ (/) e. V) -> (<.<.(/), (/)>., <.(/), (/)>.>. e. Cat <-> ((<.<.(/), (/)>., <.(/), (/)>.>. e. Ded /\ A.f e. dom (/)A.g e. dom (/)A.h e. dom (/)((((/)` h) = ((/)` g) /\ ((/)` g) = ((/)` f)) -> (h(/)(g(/)f)) = ((h(/)g)(/)f))) /\ (A.a e. dom (/)A.f e. dom (/)(((/)` f) = a -> (((/)` a)(/)f) = f) /\ A.a e. dom (/)A.f e. dom (/)(((/)` f) = a -> (f(/)((/)` a)) = f)))))
52, 1, 4mp2an 697 . 2 |- (<.<.(/), (/)>., <.(/), (/)>.>. e. Cat <-> ((<.<.(/), (/)>., <.(/), (/)>.>. e. Ded /\ A.f e. dom (/)A.g e. dom (/)A.h e. dom (/)((((/)` h) = ((/)` g) /\ ((/)`
g) = ((/)` f)) -> (h(/)(g(/)f)) = ((h(/)g)(/)f))) /\ (A.a e. dom (/)A.f e. dom (/)(((/)` f) = a -> (((/)` a)(/)f) = f) /\ A.a e. dom (/)A.f e. dom (/)(((/)` f) = a -> (f(/)((/)` a)) = f))))
6 0ded 10690 . . 3 |- <.<.(/), (/)>., <.(/), (/)>.>. e. Ded
7 dm0 3323 . . . . . 6 |- dom (/) = (/)
87eleq2i 1538 . . . . 5 |- (f e. dom (/) <-> f e. (/))
9 noel 2284 . . . . . 6 |- -. f e. (/)
109pm2.21i 77 . . . . 5 |- (f e. (/) -> A.g e. dom (/)A.h e. dom (/)((((/)` h) = ((/)` g) /\ ((/)`
g) = ((/)` f)) -> (h(/)(g(/)f)) = ((h(/)g)(/)f)))
118, 10sylbi 199 . . . 4 |- (f e. dom (/) -> A.g e. dom (/)A.h e. dom (/)((((/)` h) = ((/)` g) /\ ((/)`
g) = ((/)` f)) -> (h(/)(g(/)f)) = ((h(/)g)(/)f)))
1211rgen 1698 . . 3 |- A.f e. dom (/)A.g e. dom (/)A.h e. dom (/)((((/)` h) = ((/)` g) /\ ((/)`
g) = ((/)` f)) -> (h(/)(g(/)f)) = ((h(/)g)(/)f))
136, 12pm3.2i 285 . 2 |- (<.<.(/), (/)>., <.(/), (/)>.>. e. Ded /\ A.f e. dom (/)A.g e. dom (/)A.h e. dom (/)((((/)` h) = ((/)` g) /\ ((/)`
g) = ((/)` f)) -> (h(/)(g(/)f)) = ((h(/)g)(/)f)))
147eleq2i 1538 . . . . 5 |- (a e. dom (/) <-> a e. (/))
15 noel 2284 . . . . . 6 |- -. a e. (/)
1615pm2.21i 77 . . . . 5 |- (a e. (/) -> A.f e. dom (/)(((/)` f) = a -> (((/)` a)(/)f) = f))
1714, 16sylbi 199 . . . 4 |- (a e. dom (/) -> A.f e. dom (/)(((/)` f) = a -> (((/)` a)(/)f) = f))
1817rgen 1698 . . 3 |- A.a e. dom (/)A.f e. dom (/)(((/)` f) = a -> (((/)` a)(/)f) = f)
1915pm2.21i 77 . . . . 5 |- (a e. (/) -> A.f e. dom (/)(((/)` f) = a -> (f(/)((/)`
a)) = f))
2014, 19sylbi 199 . . . 4 |- (a e. dom (/) -> A.f e. dom (/)(((/)` f) = a -> (f(/)((/)`
a)) = f))
2120rgen 1698 . . 3 |- A.a e. dom (/)A.f e. dom (/)(((/)` f) = a -> (f(/)((/)` a)) = f)
2218, 21pm3.2i 285 . 2 |- (A.a e. dom (/)A.f e. dom (/)(((/)` f) = a -> (((/)` a)(/)f) = f) /\ A.a e. dom (/)A.f e. dom (/)(((/)` f) = a -> (f(/)((/)`
a)) = f))
235, 13, 22mpbir2an 730 1 |- <.<.(/), (/)>., <.(/), (/)>.>. e. Cat
Colors of variables: wff set class
Syntax hints:   -> wi 3   <-> wb 146   /\ wa 223   /\ w3a 775   = wceq 956   e. wcel 958  A.wral 1645  Vcvv 1811  (/)c0 2280  <.cop 2411  dom cdm 3170  ` cfv 3182  (class class class)co 3963  Dedcded 10667  Catccat 10685
This theorem was proved from axioms:  ax-1 4  ax-2 5  ax-3 6  ax-mp 7  ax-7 962  ax-gen 963  ax-8 964  ax-9 965  ax-10 966  ax-11 967  ax-12 968  ax-13 969  ax-14 970  ax-17 971  ax-4 973  ax-5o 975  ax-6o 978  ax-9o 1123  ax-10o 1140  ax-16 1210  ax-11o 1218  ax-ext 1459  ax-sep 2703  ax-nul 2710  ax-pow 2742  ax-pr 2779
This theorem depends on definitions:  df-bi 147  df-or 224  df-an 225  df-3an 777  df-ex 981  df-sb 1172  df-eu 1382  df-mo 1383  df-clab 1464  df-cleq 1469  df-clel 1472  df-ne 1587  df-ral 1649  df-v 1812  df-dif 2049  df-un 2050  df-in 2051  df-ss 2053  df-nul 2281  df-pw 2402  df-sn 2412  df-pr 2413  df-op 2416  df-uni 2504  df-br 2620  df-opab 2667  df-id 2835  df-xp 3184  df-rel 3185  df-cnv 3186  df-co 3187  df-dm 3188  df-rn 3189  df-res 3190  df-ima 3191  df-fun 3192  df-fn 3193  df-f 3194  df-fv 3198  df-opr 3965  df-alg 10648  df-ded 10668  df-cat 10686
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