Description: Confun simplified to two propositions. (Contributed by Jarvin Udandy, 6-Sep-2020)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | confun2.1 | ⊢ ( 𝜓 → 𝜑 ) | |
| confun2.2 | ⊢ ( 𝜓 → ¬ ( 𝜓 → ( 𝜓 ∧ ¬ 𝜓 ) ) ) | ||
| confun2.3 | ⊢ ( ( 𝜓 → 𝜑 ) → ( ( 𝜓 → 𝜑 ) → 𝜑 ) ) | ||
| Assertion | confun2 | ⊢ ( 𝜓 → ( ¬ ( 𝜓 → ( 𝜓 ∧ ¬ 𝜓 ) ) ↔ ( 𝜓 → 𝜑 ) ) ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | confun2.1 | ⊢ ( 𝜓 → 𝜑 ) | |
| 2 | confun2.2 | ⊢ ( 𝜓 → ¬ ( 𝜓 → ( 𝜓 ∧ ¬ 𝜓 ) ) ) | |
| 3 | confun2.3 | ⊢ ( ( 𝜓 → 𝜑 ) → ( ( 𝜓 → 𝜑 ) → 𝜑 ) ) | |
| 4 | 1 1 2 3 | confun | ⊢ ( 𝜓 → ( ¬ ( 𝜓 → ( 𝜓 ∧ ¬ 𝜓 ) ) ↔ ( 𝜓 → 𝜑 ) ) ) |