P. 15 of Theorem List - Metamath Proof Explorer

Theorem List for Metamath Proof Explorer - 1401-1500   *Has distinct variable group(s)

Type	Label	Description
Statement
Theorem	syl233anc 1401	Syllogism combined with contraction. (Contributed by NM, 11-Mar-2012.)
⊢ (𝜑 → 𝜓)    &   ⊢ (𝜑 → 𝜒)    &   ⊢ (𝜑 → 𝜃)    &   ⊢ (𝜑 → 𝜏)    &   ⊢ (𝜑 → 𝜂)    &   ⊢ (𝜑 → 𝜁)    &   ⊢ (𝜑 → 𝜎)    &   ⊢ (𝜑 → 𝜌)    &   ⊢ (((𝜓 ∧ 𝜒) ∧ (𝜃 ∧ 𝜏 ∧ 𝜂) ∧ (𝜁 ∧ 𝜎 ∧ 𝜌)) → 𝜇)    ⇒   ⊢ (𝜑 → 𝜇)
Theorem	syl323anc 1402	Syllogism combined with contraction. (Contributed by NM, 11-Mar-2012.)
⊢ (𝜑 → 𝜓)    &   ⊢ (𝜑 → 𝜒)    &   ⊢ (𝜑 → 𝜃)    &   ⊢ (𝜑 → 𝜏)    &   ⊢ (𝜑 → 𝜂)    &   ⊢ (𝜑 → 𝜁)    &   ⊢ (𝜑 → 𝜎)    &   ⊢ (𝜑 → 𝜌)    &   ⊢ (((𝜓 ∧ 𝜒 ∧ 𝜃) ∧ (𝜏 ∧ 𝜂) ∧ (𝜁 ∧ 𝜎 ∧ 𝜌)) → 𝜇)    ⇒   ⊢ (𝜑 → 𝜇)
Theorem	syl332anc 1403	Syllogism combined with contraction. (Contributed by NM, 11-Mar-2012.)
⊢ (𝜑 → 𝜓)    &   ⊢ (𝜑 → 𝜒)    &   ⊢ (𝜑 → 𝜃)    &   ⊢ (𝜑 → 𝜏)    &   ⊢ (𝜑 → 𝜂)    &   ⊢ (𝜑 → 𝜁)    &   ⊢ (𝜑 → 𝜎)    &   ⊢ (𝜑 → 𝜌)    &   ⊢ (((𝜓 ∧ 𝜒 ∧ 𝜃) ∧ (𝜏 ∧ 𝜂 ∧ 𝜁) ∧ (𝜎 ∧ 𝜌)) → 𝜇)    ⇒   ⊢ (𝜑 → 𝜇)
Theorem	syl333anc 1404	A syllogism inference combined with contraction. (Contributed by NM, 10-Mar-2012.)
⊢ (𝜑 → 𝜓)    &   ⊢ (𝜑 → 𝜒)    &   ⊢ (𝜑 → 𝜃)    &   ⊢ (𝜑 → 𝜏)    &   ⊢ (𝜑 → 𝜂)    &   ⊢ (𝜑 → 𝜁)    &   ⊢ (𝜑 → 𝜎)    &   ⊢ (𝜑 → 𝜌)    &   ⊢ (𝜑 → 𝜇)    &   ⊢ (((𝜓 ∧ 𝜒 ∧ 𝜃) ∧ (𝜏 ∧ 𝜂 ∧ 𝜁) ∧ (𝜎 ∧ 𝜌 ∧ 𝜇)) → 𝜆)    ⇒   ⊢ (𝜑 → 𝜆)
Theorem	syl3an1b 1405	A syllogism inference. (Contributed by NM, 22-Aug-1995.)
⊢ (𝜑 ↔ 𝜓)    &   ⊢ ((𝜓 ∧ 𝜒 ∧ 𝜃) → 𝜏)    ⇒   ⊢ ((𝜑 ∧ 𝜒 ∧ 𝜃) → 𝜏)
Theorem	syl3an2b 1406	A syllogism inference. (Contributed by NM, 22-Aug-1995.)
⊢ (𝜑 ↔ 𝜒)    &   ⊢ ((𝜓 ∧ 𝜒 ∧ 𝜃) → 𝜏)    ⇒   ⊢ ((𝜓 ∧ 𝜑 ∧ 𝜃) → 𝜏)
Theorem	syl3an3b 1407	A syllogism inference. (Contributed by NM, 22-Aug-1995.)
⊢ (𝜑 ↔ 𝜃)    &   ⊢ ((𝜓 ∧ 𝜒 ∧ 𝜃) → 𝜏)    ⇒   ⊢ ((𝜓 ∧ 𝜒 ∧ 𝜑) → 𝜏)
Theorem	syl3an1br 1408	A syllogism inference. (Contributed by NM, 22-Aug-1995.)
⊢ (𝜓 ↔ 𝜑)    &   ⊢ ((𝜓 ∧ 𝜒 ∧ 𝜃) → 𝜏)    ⇒   ⊢ ((𝜑 ∧ 𝜒 ∧ 𝜃) → 𝜏)
Theorem	syl3an2br 1409	A syllogism inference. (Contributed by NM, 22-Aug-1995.)
⊢ (𝜒 ↔ 𝜑)    &   ⊢ ((𝜓 ∧ 𝜒 ∧ 𝜃) → 𝜏)    ⇒   ⊢ ((𝜓 ∧ 𝜑 ∧ 𝜃) → 𝜏)
Theorem	syl3an3br 1410	A syllogism inference. (Contributed by NM, 22-Aug-1995.)
⊢ (𝜃 ↔ 𝜑)    &   ⊢ ((𝜓 ∧ 𝜒 ∧ 𝜃) → 𝜏)    ⇒   ⊢ ((𝜓 ∧ 𝜒 ∧ 𝜑) → 𝜏)
Theorem	syld3an3 1411	A syllogism inference. (Contributed by NM, 20-May-2007.)
⊢ ((𝜑 ∧ 𝜓 ∧ 𝜒) → 𝜃)    &   ⊢ ((𝜑 ∧ 𝜓 ∧ 𝜃) → 𝜏)    ⇒   ⊢ ((𝜑 ∧ 𝜓 ∧ 𝜒) → 𝜏)
Theorem	syld3an1 1412	A syllogism inference. (Contributed by NM, 7-Jul-2008.) (Proof shortened by Wolf Lammen, 26-Jun-2022.)
⊢ ((𝜒 ∧ 𝜓 ∧ 𝜃) → 𝜑)    &   ⊢ ((𝜑 ∧ 𝜓 ∧ 𝜃) → 𝜏)    ⇒   ⊢ ((𝜒 ∧ 𝜓 ∧ 𝜃) → 𝜏)
Theorem	syld3an2 1413	A syllogism inference. (Contributed by NM, 20-May-2007.)
⊢ ((𝜑 ∧ 𝜒 ∧ 𝜃) → 𝜓)    &   ⊢ ((𝜑 ∧ 𝜓 ∧ 𝜃) → 𝜏)    ⇒   ⊢ ((𝜑 ∧ 𝜒 ∧ 𝜃) → 𝜏)
Theorem	syl3anl1 1414	A syllogism inference. (Contributed by NM, 24-Feb-2005.)
⊢ (𝜑 → 𝜓)    &   ⊢ (((𝜓 ∧ 𝜒 ∧ 𝜃) ∧ 𝜏) → 𝜂)    ⇒   ⊢ (((𝜑 ∧ 𝜒 ∧ 𝜃) ∧ 𝜏) → 𝜂)
Theorem	syl3anl2 1415	A syllogism inference. (Contributed by NM, 24-Feb-2005.) (Proof shortened by Wolf Lammen, 27-Jun-2022.)
⊢ (𝜑 → 𝜒)    &   ⊢ (((𝜓 ∧ 𝜒 ∧ 𝜃) ∧ 𝜏) → 𝜂)    ⇒   ⊢ (((𝜓 ∧ 𝜑 ∧ 𝜃) ∧ 𝜏) → 𝜂)
Theorem	syl3anl3 1416	A syllogism inference. (Contributed by NM, 24-Feb-2005.)
⊢ (𝜑 → 𝜃)    &   ⊢ (((𝜓 ∧ 𝜒 ∧ 𝜃) ∧ 𝜏) → 𝜂)    ⇒   ⊢ (((𝜓 ∧ 𝜒 ∧ 𝜑) ∧ 𝜏) → 𝜂)
Theorem	syl3anl 1417	A triple syllogism inference. (Contributed by NM, 24-Dec-2006.)
⊢ (𝜑 → 𝜓)    &   ⊢ (𝜒 → 𝜃)    &   ⊢ (𝜏 → 𝜂)    &   ⊢ (((𝜓 ∧ 𝜃 ∧ 𝜂) ∧ 𝜁) → 𝜎)    ⇒   ⊢ (((𝜑 ∧ 𝜒 ∧ 𝜏) ∧ 𝜁) → 𝜎)
Theorem	syl3anr1 1418	A syllogism inference. (Contributed by NM, 31-Jul-2007.)
⊢ (𝜑 → 𝜓)    &   ⊢ ((𝜒 ∧ (𝜓 ∧ 𝜃 ∧ 𝜏)) → 𝜂)    ⇒   ⊢ ((𝜒 ∧ (𝜑 ∧ 𝜃 ∧ 𝜏)) → 𝜂)
Theorem	syl3anr2 1419	A syllogism inference. (Contributed by NM, 1-Aug-2007.) (Proof shortened by Wolf Lammen, 27-Jun-2022.)
⊢ (𝜑 → 𝜃)    &   ⊢ ((𝜒 ∧ (𝜓 ∧ 𝜃 ∧ 𝜏)) → 𝜂)    ⇒   ⊢ ((𝜒 ∧ (𝜓 ∧ 𝜑 ∧ 𝜏)) → 𝜂)
Theorem	syl3anr3 1420	A syllogism inference. (Contributed by NM, 23-Aug-2007.)
⊢ (𝜑 → 𝜏)    &   ⊢ ((𝜒 ∧ (𝜓 ∧ 𝜃 ∧ 𝜏)) → 𝜂)    ⇒   ⊢ ((𝜒 ∧ (𝜓 ∧ 𝜃 ∧ 𝜑)) → 𝜂)
Theorem	3anidm12 1421	Inference from idempotent law for conjunction. (Contributed by NM, 7-Mar-2008.)
⊢ ((𝜑 ∧ 𝜑 ∧ 𝜓) → 𝜒)    ⇒   ⊢ ((𝜑 ∧ 𝜓) → 𝜒)
Theorem	3anidm13 1422	Inference from idempotent law for conjunction. (Contributed by NM, 7-Mar-2008.)
⊢ ((𝜑 ∧ 𝜓 ∧ 𝜑) → 𝜒)    ⇒   ⊢ ((𝜑 ∧ 𝜓) → 𝜒)
Theorem	3anidm23 1423	Inference from idempotent law for conjunction. (Contributed by NM, 1-Feb-2007.)
⊢ ((𝜑 ∧ 𝜓 ∧ 𝜓) → 𝜒)    ⇒   ⊢ ((𝜑 ∧ 𝜓) → 𝜒)
Theorem	syl2an3an 1424	syl3an 1161 with antecedents in standard conjunction form. (Contributed by Alan Sare, 31-Aug-2016.)
⊢ (𝜑 → 𝜓)    &   ⊢ (𝜑 → 𝜒)    &   ⊢ (𝜃 → 𝜏)    &   ⊢ ((𝜓 ∧ 𝜒 ∧ 𝜏) → 𝜂)    ⇒   ⊢ ((𝜑 ∧ 𝜃) → 𝜂)
Theorem	syl2an23an 1425	Deduction related to syl3an 1161 with antecedents in standard conjunction form. (Contributed by Alan Sare, 31-Aug-2016.) (Proof shortened by Wolf Lammen, 28-Jun-2022.)
⊢ (𝜑 → 𝜓)    &   ⊢ (𝜑 → 𝜒)    &   ⊢ ((𝜃 ∧ 𝜑) → 𝜏)    &   ⊢ ((𝜓 ∧ 𝜒 ∧ 𝜏) → 𝜂)    ⇒   ⊢ ((𝜃 ∧ 𝜑) → 𝜂)
Theorem	3ori 1426	Infer implication from triple disjunction. (Contributed by NM, 26-Sep-2006.)
⊢ (𝜑 ∨ 𝜓 ∨ 𝜒)    ⇒   ⊢ ((¬ 𝜑 ∧ ¬ 𝜓) → 𝜒)
Theorem	3jao 1427	Disjunction of three antecedents. (Contributed by NM, 8-Apr-1994.)
⊢ (((𝜑 → 𝜓) ∧ (𝜒 → 𝜓) ∧ (𝜃 → 𝜓)) → ((𝜑 ∨ 𝜒 ∨ 𝜃) → 𝜓))
Theorem	3jaob 1428	Disjunction of three antecedents. (Contributed by NM, 13-Sep-2011.) (Proof shortened by Hongxiu Chen, 29-Jun-2025.)
⊢ (((𝜑 ∨ 𝜒 ∨ 𝜃) → 𝜓) ↔ ((𝜑 → 𝜓) ∧ (𝜒 → 𝜓) ∧ (𝜃 → 𝜓)))
Theorem	3jaobOLD 1429	Obsolete version of 3jaob 1428 as of 29-Jun-2025. (Contributed by NM, 13-Sep-2011.) (Proof modification is discouraged.) (New usage is discouraged.)
⊢ (((𝜑 ∨ 𝜒 ∨ 𝜃) → 𝜓) ↔ ((𝜑 → 𝜓) ∧ (𝜒 → 𝜓) ∧ (𝜃 → 𝜓)))
Theorem	3jaoi 1430	Disjunction of three antecedents (inference). (Contributed by NM, 12-Sep-1995.)
⊢ (𝜑 → 𝜓)    &   ⊢ (𝜒 → 𝜓)    &   ⊢ (𝜃 → 𝜓)    ⇒   ⊢ ((𝜑 ∨ 𝜒 ∨ 𝜃) → 𝜓)
Theorem	3jaod 1431	Disjunction of three antecedents (deduction). (Contributed by NM, 14-Oct-2005.)
⊢ (𝜑 → (𝜓 → 𝜒))    &   ⊢ (𝜑 → (𝜃 → 𝜒))    &   ⊢ (𝜑 → (𝜏 → 𝜒))    ⇒   ⊢ (𝜑 → ((𝜓 ∨ 𝜃 ∨ 𝜏) → 𝜒))
Theorem	3jaoian 1432	Disjunction of three antecedents (inference). (Contributed by NM, 14-Oct-2005.)
⊢ ((𝜑 ∧ 𝜓) → 𝜒)    &   ⊢ ((𝜃 ∧ 𝜓) → 𝜒)    &   ⊢ ((𝜏 ∧ 𝜓) → 𝜒)    ⇒   ⊢ (((𝜑 ∨ 𝜃 ∨ 𝜏) ∧ 𝜓) → 𝜒)
Theorem	3jaodan 1433	Disjunction of three antecedents (deduction). (Contributed by NM, 14-Oct-2005.)
⊢ ((𝜑 ∧ 𝜓) → 𝜒)    &   ⊢ ((𝜑 ∧ 𝜃) → 𝜒)    &   ⊢ ((𝜑 ∧ 𝜏) → 𝜒)    ⇒   ⊢ ((𝜑 ∧ (𝜓 ∨ 𝜃 ∨ 𝜏)) → 𝜒)
Theorem	mpjao3dan 1434	Eliminate a three-way disjunction in a deduction. (Contributed by Thierry Arnoux, 13-Apr-2018.) (Proof shortened by Wolf Lammen, 20-Apr-2024.)
⊢ ((𝜑 ∧ 𝜓) → 𝜒)    &   ⊢ ((𝜑 ∧ 𝜃) → 𝜒)    &   ⊢ ((𝜑 ∧ 𝜏) → 𝜒)    &   ⊢ (𝜑 → (𝜓 ∨ 𝜃 ∨ 𝜏))    ⇒   ⊢ (𝜑 → 𝜒)
Theorem	3jaao 1435	Inference conjoining and disjoining the antecedents of three implications. (Contributed by Jeff Hankins, 15-Aug-2009.) (Proof shortened by Andrew Salmon, 13-May-2011.)
⊢ (𝜑 → (𝜓 → 𝜒))    &   ⊢ (𝜃 → (𝜏 → 𝜒))    &   ⊢ (𝜂 → (𝜁 → 𝜒))    ⇒   ⊢ ((𝜑 ∧ 𝜃 ∧ 𝜂) → ((𝜓 ∨ 𝜏 ∨ 𝜁) → 𝜒))
Theorem	syl3an9b 1436	Nested syllogism inference conjoining 3 dissimilar antecedents. (Contributed by NM, 1-May-1995.)
⊢ (𝜑 → (𝜓 ↔ 𝜒))    &   ⊢ (𝜃 → (𝜒 ↔ 𝜏))    &   ⊢ (𝜂 → (𝜏 ↔ 𝜁))    ⇒   ⊢ ((𝜑 ∧ 𝜃 ∧ 𝜂) → (𝜓 ↔ 𝜁))
Theorem	3orbi123d 1437	Deduction joining 3 equivalences to form equivalence of disjunctions. (Contributed by NM, 20-Apr-1994.)
⊢ (𝜑 → (𝜓 ↔ 𝜒))    &   ⊢ (𝜑 → (𝜃 ↔ 𝜏))    &   ⊢ (𝜑 → (𝜂 ↔ 𝜁))    ⇒   ⊢ (𝜑 → ((𝜓 ∨ 𝜃 ∨ 𝜂) ↔ (𝜒 ∨ 𝜏 ∨ 𝜁)))
Theorem	3anbi123d 1438	Deduction joining 3 equivalences to form equivalence of conjunctions. (Contributed by NM, 22-Apr-1994.)
⊢ (𝜑 → (𝜓 ↔ 𝜒))    &   ⊢ (𝜑 → (𝜃 ↔ 𝜏))    &   ⊢ (𝜑 → (𝜂 ↔ 𝜁))    ⇒   ⊢ (𝜑 → ((𝜓 ∧ 𝜃 ∧ 𝜂) ↔ (𝜒 ∧ 𝜏 ∧ 𝜁)))
Theorem	3anbi12d 1439	Deduction conjoining and adding a conjunct to equivalences. (Contributed by NM, 8-Sep-2006.)
⊢ (𝜑 → (𝜓 ↔ 𝜒))    &   ⊢ (𝜑 → (𝜃 ↔ 𝜏))    ⇒   ⊢ (𝜑 → ((𝜓 ∧ 𝜃 ∧ 𝜂) ↔ (𝜒 ∧ 𝜏 ∧ 𝜂)))
Theorem	3anbi13d 1440	Deduction conjoining and adding a conjunct to equivalences. (Contributed by NM, 8-Sep-2006.)
⊢ (𝜑 → (𝜓 ↔ 𝜒))    &   ⊢ (𝜑 → (𝜃 ↔ 𝜏))    ⇒   ⊢ (𝜑 → ((𝜓 ∧ 𝜂 ∧ 𝜃) ↔ (𝜒 ∧ 𝜂 ∧ 𝜏)))
Theorem	3anbi23d 1441	Deduction conjoining and adding a conjunct to equivalences. (Contributed by NM, 8-Sep-2006.)
⊢ (𝜑 → (𝜓 ↔ 𝜒))    &   ⊢ (𝜑 → (𝜃 ↔ 𝜏))    ⇒   ⊢ (𝜑 → ((𝜂 ∧ 𝜓 ∧ 𝜃) ↔ (𝜂 ∧ 𝜒 ∧ 𝜏)))
Theorem	3anbi1d 1442	Deduction adding conjuncts to an equivalence. (Contributed by NM, 8-Sep-2006.)
⊢ (𝜑 → (𝜓 ↔ 𝜒))    ⇒   ⊢ (𝜑 → ((𝜓 ∧ 𝜃 ∧ 𝜏) ↔ (𝜒 ∧ 𝜃 ∧ 𝜏)))
Theorem	3anbi2d 1443	Deduction adding conjuncts to an equivalence. (Contributed by NM, 8-Sep-2006.)
⊢ (𝜑 → (𝜓 ↔ 𝜒))    ⇒   ⊢ (𝜑 → ((𝜃 ∧ 𝜓 ∧ 𝜏) ↔ (𝜃 ∧ 𝜒 ∧ 𝜏)))
Theorem	3anbi3d 1444	Deduction adding conjuncts to an equivalence. (Contributed by NM, 8-Sep-2006.)
⊢ (𝜑 → (𝜓 ↔ 𝜒))    ⇒   ⊢ (𝜑 → ((𝜃 ∧ 𝜏 ∧ 𝜓) ↔ (𝜃 ∧ 𝜏 ∧ 𝜒)))
Theorem	3anim123d 1445	Deduction joining 3 implications to form implication of conjunctions. (Contributed by NM, 24-Feb-2005.)
⊢ (𝜑 → (𝜓 → 𝜒))    &   ⊢ (𝜑 → (𝜃 → 𝜏))    &   ⊢ (𝜑 → (𝜂 → 𝜁))    ⇒   ⊢ (𝜑 → ((𝜓 ∧ 𝜃 ∧ 𝜂) → (𝜒 ∧ 𝜏 ∧ 𝜁)))
Theorem	3orim123d 1446	Deduction joining 3 implications to form implication of disjunctions. (Contributed by NM, 4-Apr-1997.)
⊢ (𝜑 → (𝜓 → 𝜒))    &   ⊢ (𝜑 → (𝜃 → 𝜏))    &   ⊢ (𝜑 → (𝜂 → 𝜁))    ⇒   ⊢ (𝜑 → ((𝜓 ∨ 𝜃 ∨ 𝜂) → (𝜒 ∨ 𝜏 ∨ 𝜁)))
Theorem	an6 1447	Rearrangement of 6 conjuncts. (Contributed by NM, 13-Mar-1995.)
⊢ (((𝜑 ∧ 𝜓 ∧ 𝜒) ∧ (𝜃 ∧ 𝜏 ∧ 𝜂)) ↔ ((𝜑 ∧ 𝜃) ∧ (𝜓 ∧ 𝜏) ∧ (𝜒 ∧ 𝜂)))
Theorem	3an6 1448	Analogue of an4 656 for triple conjunction. (Contributed by Scott Fenton, 16-Mar-2011.) (Proof shortened by Andrew Salmon, 25-May-2011.)
⊢ (((𝜑 ∧ 𝜓) ∧ (𝜒 ∧ 𝜃) ∧ (𝜏 ∧ 𝜂)) ↔ ((𝜑 ∧ 𝜒 ∧ 𝜏) ∧ (𝜓 ∧ 𝜃 ∧ 𝜂)))
Theorem	3or6 1449	Analogue of or4 927 for triple conjunction. (Contributed by Scott Fenton, 16-Mar-2011.)
⊢ (((𝜑 ∨ 𝜓) ∨ (𝜒 ∨ 𝜃) ∨ (𝜏 ∨ 𝜂)) ↔ ((𝜑 ∨ 𝜒 ∨ 𝜏) ∨ (𝜓 ∨ 𝜃 ∨ 𝜂)))
Theorem	mp3an1 1450	An inference based on modus ponens. (Contributed by NM, 21-Nov-1994.)
⊢ 𝜑    &   ⊢ ((𝜑 ∧ 𝜓 ∧ 𝜒) → 𝜃)    ⇒   ⊢ ((𝜓 ∧ 𝜒) → 𝜃)
Theorem	mp3an2 1451	An inference based on modus ponens. (Contributed by NM, 21-Nov-1994.)
⊢ 𝜓    &   ⊢ ((𝜑 ∧ 𝜓 ∧ 𝜒) → 𝜃)    ⇒   ⊢ ((𝜑 ∧ 𝜒) → 𝜃)
Theorem	mp3an3 1452	An inference based on modus ponens. (Contributed by NM, 21-Nov-1994.)
⊢ 𝜒    &   ⊢ ((𝜑 ∧ 𝜓 ∧ 𝜒) → 𝜃)    ⇒   ⊢ ((𝜑 ∧ 𝜓) → 𝜃)
Theorem	mp3an12 1453	An inference based on modus ponens. (Contributed by NM, 13-Jul-2005.)
⊢ 𝜑    &   ⊢ 𝜓    &   ⊢ ((𝜑 ∧ 𝜓 ∧ 𝜒) → 𝜃)    ⇒   ⊢ (𝜒 → 𝜃)
Theorem	mp3an13 1454	An inference based on modus ponens. (Contributed by NM, 14-Jul-2005.)
⊢ 𝜑    &   ⊢ 𝜒    &   ⊢ ((𝜑 ∧ 𝜓 ∧ 𝜒) → 𝜃)    ⇒   ⊢ (𝜓 → 𝜃)
Theorem	mp3an23 1455	An inference based on modus ponens. (Contributed by NM, 14-Jul-2005.)
⊢ 𝜓    &   ⊢ 𝜒    &   ⊢ ((𝜑 ∧ 𝜓 ∧ 𝜒) → 𝜃)    ⇒   ⊢ (𝜑 → 𝜃)
Theorem	mp3an1i 1456	An inference based on modus ponens. (Contributed by NM, 5-Jul-2005.)
⊢ 𝜓    &   ⊢ (𝜑 → ((𝜓 ∧ 𝜒 ∧ 𝜃) → 𝜏))    ⇒   ⊢ (𝜑 → ((𝜒 ∧ 𝜃) → 𝜏))
Theorem	mp3anl1 1457	An inference based on modus ponens. (Contributed by NM, 24-Feb-2005.)
⊢ 𝜑    &   ⊢ (((𝜑 ∧ 𝜓 ∧ 𝜒) ∧ 𝜃) → 𝜏)    ⇒   ⊢ (((𝜓 ∧ 𝜒) ∧ 𝜃) → 𝜏)
Theorem	mp3anl2 1458	An inference based on modus ponens. (Contributed by NM, 24-Feb-2005.)
⊢ 𝜓    &   ⊢ (((𝜑 ∧ 𝜓 ∧ 𝜒) ∧ 𝜃) → 𝜏)    ⇒   ⊢ (((𝜑 ∧ 𝜒) ∧ 𝜃) → 𝜏)
Theorem	mp3anl3 1459	An inference based on modus ponens. (Contributed by NM, 24-Feb-2005.)
⊢ 𝜒    &   ⊢ (((𝜑 ∧ 𝜓 ∧ 𝜒) ∧ 𝜃) → 𝜏)    ⇒   ⊢ (((𝜑 ∧ 𝜓) ∧ 𝜃) → 𝜏)
Theorem	mp3anr1 1460	An inference based on modus ponens. (Contributed by NM, 4-Nov-2006.)
⊢ 𝜓    &   ⊢ ((𝜑 ∧ (𝜓 ∧ 𝜒 ∧ 𝜃)) → 𝜏)    ⇒   ⊢ ((𝜑 ∧ (𝜒 ∧ 𝜃)) → 𝜏)
Theorem	mp3anr2 1461	An inference based on modus ponens. (Contributed by NM, 24-Nov-2006.)
⊢ 𝜒    &   ⊢ ((𝜑 ∧ (𝜓 ∧ 𝜒 ∧ 𝜃)) → 𝜏)    ⇒   ⊢ ((𝜑 ∧ (𝜓 ∧ 𝜃)) → 𝜏)
Theorem	mp3anr3 1462	An inference based on modus ponens. (Contributed by NM, 19-Oct-2007.)
⊢ 𝜃    &   ⊢ ((𝜑 ∧ (𝜓 ∧ 𝜒 ∧ 𝜃)) → 𝜏)    ⇒   ⊢ ((𝜑 ∧ (𝜓 ∧ 𝜒)) → 𝜏)
Theorem	mp3an 1463	An inference based on modus ponens. (Contributed by NM, 14-May-1999.)
⊢ 𝜑    &   ⊢ 𝜓    &   ⊢ 𝜒    &   ⊢ ((𝜑 ∧ 𝜓 ∧ 𝜒) → 𝜃)    ⇒   ⊢ 𝜃
Theorem	mpd3an3 1464	An inference based on modus ponens. (Contributed by NM, 8-Nov-2007.)
⊢ ((𝜑 ∧ 𝜓) → 𝜒)    &   ⊢ ((𝜑 ∧ 𝜓 ∧ 𝜒) → 𝜃)    ⇒   ⊢ ((𝜑 ∧ 𝜓) → 𝜃)
Theorem	mpd3an23 1465	An inference based on modus ponens. (Contributed by NM, 4-Dec-2006.)
⊢ (𝜑 → 𝜓)    &   ⊢ (𝜑 → 𝜒)    &   ⊢ ((𝜑 ∧ 𝜓 ∧ 𝜒) → 𝜃)    ⇒   ⊢ (𝜑 → 𝜃)
Theorem	mp3and 1466	A deduction based on modus ponens. (Contributed by Mario Carneiro, 24-Dec-2016.)
⊢ (𝜑 → 𝜓)    &   ⊢ (𝜑 → 𝜒)    &   ⊢ (𝜑 → 𝜃)    &   ⊢ (𝜑 → ((𝜓 ∧ 𝜒 ∧ 𝜃) → 𝜏))    ⇒   ⊢ (𝜑 → 𝜏)
Theorem	mp3an12i 1467	mp3an 1463 with antecedents in standard conjunction form and with one hypothesis an implication. (Contributed by Alan Sare, 28-Aug-2016.)
⊢ 𝜑    &   ⊢ 𝜓    &   ⊢ (𝜒 → 𝜃)    &   ⊢ ((𝜑 ∧ 𝜓 ∧ 𝜃) → 𝜏)    ⇒   ⊢ (𝜒 → 𝜏)
Theorem	mp3an2i 1468	mp3an 1463 with antecedents in standard conjunction form and with two hypotheses which are implications. (Contributed by Alan Sare, 28-Aug-2016.)
⊢ 𝜑    &   ⊢ (𝜓 → 𝜒)    &   ⊢ (𝜓 → 𝜃)    &   ⊢ ((𝜑 ∧ 𝜒 ∧ 𝜃) → 𝜏)    ⇒   ⊢ (𝜓 → 𝜏)
Theorem	mp3an3an 1469	mp3an 1463 with antecedents in standard conjunction form and with two hypotheses which are implications. (Contributed by Alan Sare, 28-Aug-2016.)
⊢ 𝜑    &   ⊢ (𝜓 → 𝜒)    &   ⊢ (𝜃 → 𝜏)    &   ⊢ ((𝜑 ∧ 𝜒 ∧ 𝜏) → 𝜂)    ⇒   ⊢ ((𝜓 ∧ 𝜃) → 𝜂)
Theorem	mp3an2ani 1470	An elimination deduction. (Contributed by Alan Sare, 17-Oct-2017.)
⊢ 𝜑    &   ⊢ (𝜓 → 𝜒)    &   ⊢ ((𝜓 ∧ 𝜃) → 𝜏)    &   ⊢ ((𝜑 ∧ 𝜒 ∧ 𝜏) → 𝜂)    ⇒   ⊢ ((𝜓 ∧ 𝜃) → 𝜂)
Theorem	biimp3a 1471	Infer implication from a logical equivalence. Similar to biimpa 476. (Contributed by NM, 4-Sep-2005.)
⊢ ((𝜑 ∧ 𝜓) → (𝜒 ↔ 𝜃))    ⇒   ⊢ ((𝜑 ∧ 𝜓 ∧ 𝜒) → 𝜃)
Theorem	biimp3ar 1472	Infer implication from a logical equivalence. Similar to biimpar 477. (Contributed by NM, 2-Jan-2009.)
⊢ ((𝜑 ∧ 𝜓) → (𝜒 ↔ 𝜃))    ⇒   ⊢ ((𝜑 ∧ 𝜓 ∧ 𝜃) → 𝜒)
Theorem	3anandis 1473	Inference that undistributes a triple conjunction in the antecedent. (Contributed by NM, 18-Apr-2007.)
⊢ (((𝜑 ∧ 𝜓) ∧ (𝜑 ∧ 𝜒) ∧ (𝜑 ∧ 𝜃)) → 𝜏)    ⇒   ⊢ ((𝜑 ∧ (𝜓 ∧ 𝜒 ∧ 𝜃)) → 𝜏)
Theorem	3anandirs 1474	Inference that undistributes a triple conjunction in the antecedent. (Contributed by NM, 25-Jul-2006.)
⊢ (((𝜑 ∧ 𝜃) ∧ (𝜓 ∧ 𝜃) ∧ (𝜒 ∧ 𝜃)) → 𝜏)    ⇒   ⊢ (((𝜑 ∧ 𝜓 ∧ 𝜒) ∧ 𝜃) → 𝜏)
Theorem	ecase23d 1475	Deduction for elimination by cases. (Contributed by NM, 22-Apr-1994.)
⊢ (𝜑 → ¬ 𝜒)    &   ⊢ (𝜑 → ¬ 𝜃)    &   ⊢ (𝜑 → (𝜓 ∨ 𝜒 ∨ 𝜃))    ⇒   ⊢ (𝜑 → 𝜓)
Theorem	3ecase 1476	Inference for elimination by cases. (Contributed by NM, 13-Jul-2005.)
⊢ (¬ 𝜑 → 𝜃)    &   ⊢ (¬ 𝜓 → 𝜃)    &   ⊢ (¬ 𝜒 → 𝜃)    &   ⊢ ((𝜑 ∧ 𝜓 ∧ 𝜒) → 𝜃)    ⇒   ⊢ 𝜃
Theorem	3bior1fd 1477	A disjunction is equivalent to a threefold disjunction with single falsehood, analogous to biorf 937. (Contributed by Alexander van der Vekens, 8-Sep-2017.)
⊢ (𝜑 → ¬ 𝜃)    ⇒   ⊢ (𝜑 → ((𝜒 ∨ 𝜓) ↔ (𝜃 ∨ 𝜒 ∨ 𝜓)))
Theorem	3bior1fand 1478	A disjunction is equivalent to a threefold disjunction with single falsehood of a conjunction. (Contributed by Alexander van der Vekens, 8-Sep-2017.)
⊢ (𝜑 → ¬ 𝜃)    ⇒   ⊢ (𝜑 → ((𝜒 ∨ 𝜓) ↔ ((𝜃 ∧ 𝜏) ∨ 𝜒 ∨ 𝜓)))
Theorem	3bior2fd 1479	A wff is equivalent to its threefold disjunction with double falsehood, analogous to biorf 937. (Contributed by Alexander van der Vekens, 8-Sep-2017.)
⊢ (𝜑 → ¬ 𝜃)    &   ⊢ (𝜑 → ¬ 𝜒)    ⇒   ⊢ (𝜑 → (𝜓 ↔ (𝜃 ∨ 𝜒 ∨ 𝜓)))
Theorem	3biant1d 1480	A conjunction is equivalent to a threefold conjunction with single truth, analogous to biantrud 531. (Contributed by Alexander van der Vekens, 26-Sep-2017.)
⊢ (𝜑 → 𝜃)    ⇒   ⊢ (𝜑 → ((𝜒 ∧ 𝜓) ↔ (𝜃 ∧ 𝜒 ∧ 𝜓)))
Theorem	intn3an1d 1481	Introduction of a triple conjunct inside a contradiction. (Contributed by FL, 27-Dec-2007.) (Proof shortened by Andrew Salmon, 26-Jun-2011.)
⊢ (𝜑 → ¬ 𝜓)    ⇒   ⊢ (𝜑 → ¬ (𝜓 ∧ 𝜒 ∧ 𝜃))
Theorem	intn3an2d 1482	Introduction of a triple conjunct inside a contradiction. (Contributed by FL, 27-Dec-2007.) (Proof shortened by Andrew Salmon, 26-Jun-2011.)
⊢ (𝜑 → ¬ 𝜓)    ⇒   ⊢ (𝜑 → ¬ (𝜒 ∧ 𝜓 ∧ 𝜃))
Theorem	intn3an3d 1483	Introduction of a triple conjunct inside a contradiction. (Contributed by FL, 27-Dec-2007.) (Proof shortened by Andrew Salmon, 26-Jun-2011.)
⊢ (𝜑 → ¬ 𝜓)    ⇒   ⊢ (𝜑 → ¬ (𝜒 ∧ 𝜃 ∧ 𝜓))
Theorem	an3andi 1484	Distribution of conjunction over threefold conjunction. (Contributed by Thierry Arnoux, 8-Apr-2019.)
⊢ ((𝜑 ∧ (𝜓 ∧ 𝜒 ∧ 𝜃)) ↔ ((𝜑 ∧ 𝜓) ∧ (𝜑 ∧ 𝜒) ∧ (𝜑 ∧ 𝜃)))
Theorem	an33rean 1485	Rearrange a 9-fold conjunction. (Contributed by Thierry Arnoux, 14-Apr-2019.) (Proof shortened by Wolf Lammen, 21-Apr-2024.)
⊢ (((𝜑 ∧ 𝜓 ∧ 𝜒) ∧ (𝜃 ∧ 𝜏 ∧ 𝜂) ∧ (𝜁 ∧ 𝜎 ∧ 𝜌)) ↔ ((𝜑 ∧ 𝜏 ∧ 𝜌) ∧ ((𝜓 ∧ 𝜃) ∧ (𝜂 ∧ 𝜎) ∧ (𝜒 ∧ 𝜁))))
Theorem	3orel2 1486	Partial elimination of a triple disjunction by denial of a disjunct. (Contributed by Scott Fenton, 26-Mar-2011.) (Proof shortened by Andrew Salmon, 25-May-2011.) (Proof shortened by Eric Schmidt, 8-Oct-2025.)
⊢ (¬ 𝜓 → ((𝜑 ∨ 𝜓 ∨ 𝜒) → (𝜑 ∨ 𝜒)))
Theorem	3orel2OLD 1487	Obsolete version of 3orel2 1486 as of 8-Oct-2025. (Contributed by Scott Fenton, 26-Mar-2011.) (Proof shortened by Andrew Salmon, 25-May-2011.) (Proof modification is discouraged.) (New usage is discouraged.)
⊢ (¬ 𝜓 → ((𝜑 ∨ 𝜓 ∨ 𝜒) → (𝜑 ∨ 𝜒)))
Theorem	3orel3 1488	Partial elimination of a triple disjunction by denial of a disjunct. (Contributed by Scott Fenton, 26-Mar-2011.)
⊢ (¬ 𝜒 → ((𝜑 ∨ 𝜓 ∨ 𝜒) → (𝜑 ∨ 𝜓)))
Theorem	3orel13 1489	Elimination of two disjuncts in a triple disjunction. (Contributed by Scott Fenton, 9-Jun-2011.)
⊢ ((¬ 𝜑 ∧ ¬ 𝜒) → ((𝜑 ∨ 𝜓 ∨ 𝜒) → 𝜓))
Theorem	3pm3.2ni 1490	Triple negated disjunction introduction. (Contributed by Scott Fenton, 20-Apr-2011.)
⊢ ¬ 𝜑    &   ⊢ ¬ 𝜓    &   ⊢ ¬ 𝜒    ⇒   ⊢ ¬ (𝜑 ∨ 𝜓 ∨ 𝜒)
1.2.12  Logical "nand" (Sheffer stroke)
Syntax	wnan 1491	Extend wff definition to include alternative denial ("nand").
wff (𝜑 ⊼ 𝜓)
Definition	df-nan 1492	Define incompatibility, or alternative denial ("not-and" or "nand"). See dfnan2 1494 for an alternative. This is also called the Sheffer stroke, represented by a vertical bar, but we use a different symbol to avoid ambiguity with other uses of the vertical bar. In the second edition of Principia Mathematica (1927), Russell and Whitehead used the Sheffer stroke and suggested it as a replacement for the "or" and "not" operations of the first edition. However, in practice, "or" and "not" are more widely used. After we define the constant true ⊤ (df-tru 1543) and the constant false ⊥ (df-fal 1553), we will be able to prove these truth table values: ((⊤ ⊼ ⊤) ↔ ⊥) (trunantru 1581), ((⊤ ⊼ ⊥) ↔ ⊤) (trunanfal 1582), ((⊥ ⊼ ⊤) ↔ ⊤) (falnantru 1583), and ((⊥ ⊼ ⊥) ↔ ⊤) (falnanfal 1584). Contrast with ∧ (df-an 396), ∨ (df-or 849), → (wi 4), and ⊻ (df-xor 1512). (Contributed by Jeff Hoffman, 19-Nov-2007.)
⊢ ((𝜑 ⊼ 𝜓) ↔ ¬ (𝜑 ∧ 𝜓))
Theorem	nanan 1493	Conjunction in terms of alternative denial. (Contributed by Mario Carneiro, 9-May-2015.)
⊢ ((𝜑 ∧ 𝜓) ↔ ¬ (𝜑 ⊼ 𝜓))
Theorem	dfnan2 1494	Alternative denial in terms of our primitive connectives (implication and negation). (Contributed by WL, 26-Jun-2020.)
⊢ ((𝜑 ⊼ 𝜓) ↔ (𝜑 → ¬ 𝜓))
Theorem	nanor 1495	Alternative denial in terms of disjunction and negation. This explains the name "alternative denial". (Contributed by BJ, 19-Oct-2022.)
⊢ ((𝜑 ⊼ 𝜓) ↔ (¬ 𝜑 ∨ ¬ 𝜓))
Theorem	nancom 1496	Alternative denial is commutative. Remark: alternative denial is not associative, see nanass 1510. (Contributed by Mario Carneiro, 9-May-2015.) (Proof shortened by Wolf Lammen, 26-Jun-2020.)
⊢ ((𝜑 ⊼ 𝜓) ↔ (𝜓 ⊼ 𝜑))
Theorem	nannan 1497	Nested alternative denials. (Contributed by Jeff Hoffman, 19-Nov-2007.) (Proof shortened by Wolf Lammen, 26-Jun-2020.)
⊢ ((𝜑 ⊼ (𝜓 ⊼ 𝜒)) ↔ (𝜑 → (𝜓 ∧ 𝜒)))
Theorem	nanim 1498	Implication in terms of alternative denial. (Contributed by Jeff Hoffman, 19-Nov-2007.)
⊢ ((𝜑 → 𝜓) ↔ (𝜑 ⊼ (𝜓 ⊼ 𝜓)))
Theorem	nannot 1499	Negation in terms of alternative denial. (Contributed by Jeff Hoffman, 19-Nov-2007.) Use dfnan2 1494. (Revised by Wolf Lammen, 26-Jun-2020.)
⊢ (¬ 𝜑 ↔ (𝜑 ⊼ 𝜑))
Theorem	nanbi 1500	Biconditional in terms of alternative denial. (Contributed by Jeff Hoffman, 19-Nov-2007.) (Proof shortened by Wolf Lammen, 27-Jun-2020.)
⊢ ((𝜑 ↔ 𝜓) ↔ ((𝜑 ⊼ 𝜓) ⊼ ((𝜑 ⊼ 𝜑) ⊼ (𝜓 ⊼ 𝜓))))