Theorem barocoALT 2707

Description: Alternate proof of festino 2704, shorter but using more axioms. See comment of dariiALT 2696. (Contributed by David A. Wheeler, 27-Aug-2016.) (Proof modification is discouraged.) (New usage is discouraged.)

Hypotheses

Ref	Expression
baroco.maj	⊢ ∀𝑥(𝜑 → 𝜓)
baroco.min	⊢ ∃𝑥(𝜒 ∧ ¬ 𝜓)

Assertion

Ref	Expression
barocoALT	⊢ ∃𝑥(𝜒 ∧ ¬ 𝜑)

Proof of Theorem barocoALT

Step	Hyp	Ref	Expression
1		baroco.min	. 2 ⊢ ∃𝑥(𝜒 ∧ ¬ 𝜓)
2		baroco.maj	. . . . 5 ⊢ ∀𝑥(𝜑 → 𝜓)
3	2	spi 2223	. . . 4 ⊢ (𝜑 → 𝜓)
4	3	con3i 155	. . 3 ⊢ (¬ 𝜓 → ¬ 𝜑)
5	4	anim2i 629	. 2 ⊢ ((𝜒 ∧ ¬ 𝜓) → (𝜒 ∧ ¬ 𝜑))
6	1, 5	eximii 1870	1 ⊢ ∃𝑥(𝜒 ∧ ¬ 𝜑)

This proof depends on syntax axioms:  ¬ wn 3   → wi 4   ∧ wa 401  ∀wal 1568  ∃wex 1812

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1943  ax-6 2000  ax-7 2041  ax-12 2216

This proof depends on definitions:  df-bi 210  df-an 402  df-ex 1813

This theorem is used by: (None)