Metamath Proof Explorer


Theorem ispod

Description: Sufficient conditions for a partial order. (Contributed by NM, 9-Jul-2014)

Ref Expression
Hypotheses ispod.1 φ x A ¬ x R x
ispod.2 φ x A y A z A x R y y R z x R z
Assertion ispod φ R Po A

Proof

Step Hyp Ref Expression
1 ispod.1 φ x A ¬ x R x
2 ispod.2 φ x A y A z A x R y y R z x R z
3 1 3ad2antr1 φ x A y A z A ¬ x R x
4 3 2 jca φ x A y A z A ¬ x R x x R y y R z x R z
5 4 ralrimivvva φ x A y A z A ¬ x R x x R y y R z x R z
6 df-po R Po A x A y A z A ¬ x R x x R y y R z x R z
7 5 6 sylibr φ R Po A