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Theorem emptar 15231
Description: A non empty Tarski's class contains the empty set.
Assertion
Ref Expression
emptar |- ((T e. Tarski /\ T =/= (/)) -> (/) e. T)

Proof of Theorem emptar
StepHypRef Expression
1 n0 2884 . . . 4 |- (T =/= (/) <-> E.x x e. T)
21biimpi 168 . . 3 |- (T =/= (/) -> E.x x e. T)
32adantl 424 . 2 |- ((T e. Tarski /\ T =/= (/)) -> E.x x e. T)
4 tarax1 15216 . . . . . . 7 |- ((T e. Tarski /\ x e. T) -> ~Px C_ T)
5 0elpw 3473 . . . . . . . 8 |- (/) e. ~Px
6 ssel 2615 . . . . . . . 8 |- (~Px C_ T -> ((/) e. ~Px -> (/) e. T))
75, 6mpi 55 . . . . . . 7 |- (~Px C_ T -> (/) e. T)
84, 7syl 12 . . . . . 6 |- ((T e. Tarski /\ x e. T) -> (/) e. T)
98ex 402 . . . . 5 |- (T e. Tarski -> (x e. T -> (/) e. T))
109adantr 425 . . . 4 |- ((T e. Tarski /\ T =/= (/)) -> (x e. T -> (/) e. T))
1110com12 14 . . 3 |- (x e. T -> ((T e. Tarski /\ T =/= (/)) -> (/) e. T))
121119.23aiv 1674 . 2 |- (E.x x e. T -> ((T e. Tarski /\ T =/= (/)) -> (/) e. T))
133, 12mpcom 60 1 |- ((T e. Tarski /\ T =/= (/)) -> (/) e. T)
Colors of variables: wff set class
Syntax hints:   -> wi 3   /\ wa 240   e. wcel 1300  E.wex 1326   =/= wne 2017   C_ wss 2593  (/)c0 2875  ~Pcpw 3032   Tarski ctarski 15208
This theorem is referenced by:  tarone 15232  cptarc 15242  cartarlim 15282
This theorem was proved from axioms:  ax-1 4  ax-2 5  ax-3 6  ax-mp 7  ax-7 1304  ax-gen 1305  ax-8 1306  ax-9 1307  ax-10 1308  ax-11 1309  ax-12 1310  ax-17 1317  ax-4 1319  ax-5o 1321  ax-6o 1324  ax-9o 1481  ax-10o 1500  ax-16 1580  ax-11o 1588  ax-ext 1865  ax-nul 3445
This theorem depends on definitions:  df-bi 164  df-or 241  df-an 242  df-ex 1327  df-sb 1536  df-clab 1872  df-cleq 1877  df-clel 1880  df-ne 2019  df-ral 2109  df-rex 2110  df-v 2294  df-dif 2597  df-un 2600  df-in 2603  df-ss 2605  df-nul 2876  df-pw 3035  df-sn 3049  df-pr 3050  df-op 3053  df-br 3339  df-tsk 15210
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