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Related theorems GIF version |
| Description: Inference chaining two syllogisms. |
| Ref | Expression |
|---|---|
| 3syl.1 | ⊢ (φ → ψ) |
| 3syl.2 | ⊢ (ψ → χ) |
| 3syl.3 | ⊢ (χ → θ) |
| Ref | Expression |
|---|---|
| 3syl | ⊢ (φ → θ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | 3syl.1 | . . 3 ⊢ (φ → ψ) | |
| 2 | 3syl.2 | . . 3 ⊢ (ψ → χ) | |
| 3 | 1, 2 | syl 12 | . 2 ⊢ (φ → χ) |
| 4 | 3syl.3 | . 2 ⊢ (χ → θ) | |
| 5 | 3, 4 | syl 12 | 1 ⊢ (φ → θ) |