Metamath Proof Explorer


Theorem ltwenn

Description: Less than well-orders the naturals. (Contributed by Scott Fenton, 6-Aug-2013)

Ref Expression
Assertion ltwenn < We ℕ

Proof

Step Hyp Ref Expression
1 ltweuz < We ( ℤ ‘ 1 )
2 nnuz ℕ = ( ℤ ‘ 1 )
3 weeq2 ( ℕ = ( ℤ ‘ 1 ) → ( < We ℕ ↔ < We ( ℤ ‘ 1 ) ) )
4 2 3 ax-mp ( < We ℕ ↔ < We ( ℤ ‘ 1 ) )
5 1 4 mpbir < We ℕ