HomeHome Metamath Proof Explorer < Previous   Next >
Related theorems
Unicode version

Theorem peano1 3112
Description: Zero is a natural number. One of Peano's 5 postulates for arithmetic. Proposition 7.30(1) of [TakeutiZaring] p. 42. Note: Unlike most textbooks, our proofs of peano1 3112 through peano5 3116 do not use the Axiom of Infinity. Unlike Takeuti and Zaring, they also do not use the Axiom of Regularity.
Assertion
Ref Expression
peano1 |- (/) e. om

Proof of Theorem peano1
StepHypRef Expression
1 limom 3109 . 2 |- Lim om
2 0ellim 2994 . 2 |- (Lim om -> (/) e. om)
31, 2ax-mp 7 1 |- (/) e. om
Colors of variables: wff set class
Syntax hints:   e. wcel 1105  (/)c0 2251  Lim wlim 2912  omcom 3094
This theorem is referenced by:  fr0t 3891  nnmcl 4168  nnecl 4169  nnmsucr 4178  1onn 4191  nneob 4193  snfi 4367  0sdom1dom 4456  infn0 4464  unblem2 4470  unfilem3 4478  unifi 4484  inf0 4530  infeq5 4545  axinf2 4548  dfom3 4554  noinfep 4564  trcl 4569  cardlim 4774  alephgeom 4805  alephfplem4 4822  mulclpi 4944  1lt2pi 4955  om2uzran 6188  uzrdgini 6191
This theorem was proved from axioms:  ax-1 4  ax-2 5  ax-3 6  ax-mp 7  ax-4 951  ax-5 952  ax-6 953  ax-7 954  ax-gen 955  ax-8 1101  ax-9 1102  ax-10 1103  ax-12 1104  ax-13 1107  ax-14 1108  ax-11 1180  ax-17 1190  ax-16 1194  ax-11o 1202  ax-ext 1436  ax-sep 2671  ax-nul 2678  ax-pow 2710  ax-pr 2747  ax-un 2830
This theorem depends on definitions:  df-bi 147  df-or 224  df-an 225  df-3or 773  df-3an 774  df-ex 957  df-sb 1155  df-eu 1359  df-mo 1360  df-clab 1441  df-cleq 1446  df-clel 1449  df-ne 1563  df-ral 1625  df-rex 1626  df-v 1787  df-dif 2020  df-un 2021  df-in 2022  df-ss 2024  df-nul 2252  df-pw 2373  df-sn 2383  df-pr 2384  df-tp 2386  df-op 2387  df-uni 2472  df-br 2588  df-opab 2635  df-tr 2649  df-eprel 2794  df-po 2804  df-so 2814  df-fr 2880  df-we 2897  df-ord 2914  df-on 2915  df-lim 2916  df-suc 2917  df-om 3095
Copyright terms: Public domain