Theorem festino 2571

Description: "Festino", one of the syllogisms of Aristotelian logic. No 𝜑 is 𝜓, and some 𝜒 is 𝜓, therefore some 𝜒 is not 𝜑. (In Aristotelian notation, EIO-2: PeM and SiM therefore SoP.) (Contributed by David A. Wheeler, 25-Nov-2016.)

Hypotheses

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

Assertion

Ref	Expression
festino	⊢ ∃𝑥(𝜒 ∧ ¬ 𝜑)

Proof of Theorem festino

Step	Hyp	Ref	Expression
1		festino.min	. 2 ⊢ ∃𝑥(𝜒 ∧ 𝜓)
2		festino.maj	. . . . 5 ⊢ ∀𝑥(𝜑 → ¬ 𝜓)
3	2	spi 2054	. . . 4 ⊢ (𝜑 → ¬ 𝜓)
4	3	con2i 134	. . 3 ⊢ (𝜓 → ¬ 𝜑)
5	4	anim2i 593	. 2 ⊢ ((𝜒 ∧ 𝜓) → (𝜒 ∧ ¬ 𝜑))
6	1, 5	eximii 1764	1 ⊢ ∃𝑥(𝜒 ∧ ¬ 𝜑)

Syntax hints:  ¬ wn 3   → wi 4   ∧ wa 384  ∀wal 1481  ∃wex 1704

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1722  ax-4 1737  ax-5 1839  ax-6 1888  ax-7 1935  ax-12 2047

This theorem depends on definitions:  df-bi 197  df-an 386  df-ex 1705

This theorem is referenced by: (None)