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Theorem List for Metamath Proof Explorer - 42501-42600   *Has distinct variable group(s)
TypeLabelDescription
Statement
 
21.36.6  Arithmetic
 
Theoremaddcomgi 42501 Generalization of commutative law for addition. Simplifies proofs dealing with vectors. However, it is dependent on our particular definition of ordered pair. (Contributed by Andrew Salmon, 28-Jan-2012.) (Revised by Mario Carneiro, 6-May-2015.)
(๐ด + ๐ต) = (๐ต + ๐ด)
 
21.36.7  Geometry
 
Syntaxcplusr 42502 Introduce the operation of vector addition.
class +๐‘Ÿ
 
Syntaxcminusr 42503 Introduce the operation of vector subtraction.
class -๐‘Ÿ
 
Syntaxctimesr 42504 Introduce the operation of scalar multiplication.
class .๐‘ฃ
 
Syntaxcptdfc 42505 PtDf is a predicate that is crucial for the definition of lines as well as proving a number of important theorems.
class PtDf(๐ด, ๐ต)
 
Syntaxcrr3c 42506 RR3 is a class.
class RR3
 
Syntaxcline3 42507 line3 is a class.
class line3
 
Definitiondf-addr 42508* Define the operation of vector addition. (Contributed by Andrew Salmon, 27-Jan-2012.)
+๐‘Ÿ = (๐‘ฅ โˆˆ V, ๐‘ฆ โˆˆ V โ†ฆ (๐‘ฃ โˆˆ โ„ โ†ฆ ((๐‘ฅโ€˜๐‘ฃ) + (๐‘ฆโ€˜๐‘ฃ))))
 
Definitiondf-subr 42509* Define the operation of vector subtraction. (Contributed by Andrew Salmon, 27-Jan-2012.)
-๐‘Ÿ = (๐‘ฅ โˆˆ V, ๐‘ฆ โˆˆ V โ†ฆ (๐‘ฃ โˆˆ โ„ โ†ฆ ((๐‘ฅโ€˜๐‘ฃ) โˆ’ (๐‘ฆโ€˜๐‘ฃ))))
 
Definitiondf-mulv 42510* Define the operation of scalar multiplication. (Contributed by Andrew Salmon, 27-Jan-2012.)
.๐‘ฃ = (๐‘ฅ โˆˆ V, ๐‘ฆ โˆˆ V โ†ฆ (๐‘ฃ โˆˆ โ„ โ†ฆ (๐‘ฅ ยท (๐‘ฆโ€˜๐‘ฃ))))
 
Theoremaddrval 42511* Value of the operation of vector addition. (Contributed by Andrew Salmon, 27-Jan-2012.)
((๐ด โˆˆ ๐ถ โˆง ๐ต โˆˆ ๐ท) โ†’ (๐ด+๐‘Ÿ๐ต) = (๐‘ฃ โˆˆ โ„ โ†ฆ ((๐ดโ€˜๐‘ฃ) + (๐ตโ€˜๐‘ฃ))))
 
Theoremsubrval 42512* Value of the operation of vector subtraction. (Contributed by Andrew Salmon, 27-Jan-2012.)
((๐ด โˆˆ ๐ถ โˆง ๐ต โˆˆ ๐ท) โ†’ (๐ด-๐‘Ÿ๐ต) = (๐‘ฃ โˆˆ โ„ โ†ฆ ((๐ดโ€˜๐‘ฃ) โˆ’ (๐ตโ€˜๐‘ฃ))))
 
Theoremmulvval 42513* Value of the operation of scalar multiplication. (Contributed by Andrew Salmon, 27-Jan-2012.)
((๐ด โˆˆ ๐ถ โˆง ๐ต โˆˆ ๐ท) โ†’ (๐ด.๐‘ฃ๐ต) = (๐‘ฃ โˆˆ โ„ โ†ฆ (๐ด ยท (๐ตโ€˜๐‘ฃ))))
 
Theoremaddrfv 42514 Vector addition at a value. The operation takes each vector ๐ด and ๐ต and forms a new vector whose values are the sum of each of the values of ๐ด and ๐ต. (Contributed by Andrew Salmon, 27-Jan-2012.)
((๐ด โˆˆ ๐ธ โˆง ๐ต โˆˆ ๐ท โˆง ๐ถ โˆˆ โ„) โ†’ ((๐ด+๐‘Ÿ๐ต)โ€˜๐ถ) = ((๐ดโ€˜๐ถ) + (๐ตโ€˜๐ถ)))
 
Theoremsubrfv 42515 Vector subtraction at a value. (Contributed by Andrew Salmon, 27-Jan-2012.)
((๐ด โˆˆ ๐ธ โˆง ๐ต โˆˆ ๐ท โˆง ๐ถ โˆˆ โ„) โ†’ ((๐ด-๐‘Ÿ๐ต)โ€˜๐ถ) = ((๐ดโ€˜๐ถ) โˆ’ (๐ตโ€˜๐ถ)))
 
Theoremmulvfv 42516 Scalar multiplication at a value. (Contributed by Andrew Salmon, 27-Jan-2012.)
((๐ด โˆˆ ๐ธ โˆง ๐ต โˆˆ ๐ท โˆง ๐ถ โˆˆ โ„) โ†’ ((๐ด.๐‘ฃ๐ต)โ€˜๐ถ) = (๐ด ยท (๐ตโ€˜๐ถ)))
 
Theoremaddrfn 42517 Vector addition produces a function. (Contributed by Andrew Salmon, 27-Jan-2012.)
((๐ด โˆˆ ๐ถ โˆง ๐ต โˆˆ ๐ท) โ†’ (๐ด+๐‘Ÿ๐ต) Fn โ„)
 
Theoremsubrfn 42518 Vector subtraction produces a function. (Contributed by Andrew Salmon, 27-Jan-2012.)
((๐ด โˆˆ ๐ถ โˆง ๐ต โˆˆ ๐ท) โ†’ (๐ด-๐‘Ÿ๐ต) Fn โ„)
 
Theoremmulvfn 42519 Scalar multiplication producees a function. (Contributed by Andrew Salmon, 27-Jan-2012.)
((๐ด โˆˆ ๐ถ โˆง ๐ต โˆˆ ๐ท) โ†’ (๐ด.๐‘ฃ๐ต) Fn โ„)
 
Theoremaddrcom 42520 Vector addition is commutative. (Contributed by Andrew Salmon, 28-Jan-2012.)
((๐ด โˆˆ ๐ถ โˆง ๐ต โˆˆ ๐ท) โ†’ (๐ด+๐‘Ÿ๐ต) = (๐ต+๐‘Ÿ๐ด))
 
Definitiondf-ptdf 42521* Define the predicate PtDf, which is a utility definition used to shorten definitions and simplify proofs. (Contributed by Andrew Salmon, 15-Jul-2012.)
PtDf(๐ด, ๐ต) = (๐‘ฅ โˆˆ โ„ โ†ฆ (((๐‘ฅ.๐‘ฃ(๐ต-๐‘Ÿ๐ด)) +๐‘ฃ ๐ด) โ€œ {1, 2, 3}))
 
Definitiondf-rr3 42522 Define the set of all points RR3. We define each point ๐ด as a function to allow the use of vector addition and subtraction as well as scalar multiplication in our proofs. (Contributed by Andrew Salmon, 15-Jul-2012.)
RR3 = (โ„ โ†‘m {1, 2, 3})
 
Definitiondf-line3 42523* Define the set of all lines. A line is an infinite subset of RR3 that satisfies a PtDf property. (Contributed by Andrew Salmon, 15-Jul-2012.)
line3 = {๐‘ฅ โˆˆ ๐’ซ RR3 โˆฃ (2o โ‰ผ ๐‘ฅ โˆง โˆ€๐‘ฆ โˆˆ ๐‘ฅ โˆ€๐‘ง โˆˆ ๐‘ฅ (๐‘ง โ‰  ๐‘ฆ โ†’ ran PtDf(๐‘ฆ, ๐‘ง) = ๐‘ฅ))}
 
21.37  Mathbox for Alan Sare

We are sad to report the passing of long-time contributor Alan Sare (Nov. 9, 1954 - Mar. 23, 2019).

Alan's first contribution to Metamath was a shorter proof for tfrlem8 8298 in 2008.

He developed a tool called "completeusersproof" that assists developing proofs using his "virtual deduction" method: https://us.metamath.org/other.html#completeusersproof 8298. His virtual deduction method is explained in the comment for wvd1 42616.

Below are some excerpts from his first emails to NM in 2007:

...I have been interested in proving set theory theorems for many years for mental exercise. I enjoy it. I have used a book by Martin Zuckerman. It is informal. I am interested in completely and perfectly proving theorems. Mr. Zuckerman leaves out most of the steps of a proof, of course, like most authors do, as you have noted. A complete proof for higher theorems would require a volume of writing similar to the Metamath documents. So I am frustrated when I am not capable of constructing a proof and Zuckerman leaves out steps I do not understand. I could search for the steps in other texts, but I don't do that too much. Metamath may be the answer for me....

...If we go beyond mathematics, I believe that it is possible to write down all human knowledge in a way similar to the way you have explicated large areas of mathematics. Of course, that would be a much, much more difficult job. For example, it is possible to take a hard science like physics, construct axioms based on experimental results, and to cast all of physics into a collection of axioms and theorems. Maybe this has already been attempted, although I am not familiar with it. When one then moves on to the soft sciences such as social science, this job gets much more difficult. The key is: All human thought consists of logical operations on abstract objects. Usually, these logical operations are done informally. There is no reason why one cannot take any subject and explicate it and take it down to the indivisible postulates in a formal rigorous way....

...When I read a math book or an engineering book I come across something I don't understand and I am compelled to understand it. But, often it is hopeless. I don't have the time. Or, I would have to read the same thing by multiple authors in the hope that different authors would give parts of the working proof that others have omitted. It is very inefficient. Because I have always been inclined to "get to the bottom" for a 100% fully understood proof....

 
21.37.1  Auxiliary theorems for the Virtual Deduction tool
 
TheoremidiALT 42524 Placeholder for idi 1. Though unnecessary, this theorem is sometimes used in proofs in this mathbox for pedagogical purposes. (Contributed by Alan Sare, 31-Dec-2011.) (Proof modification is discouraged.) (New usage is discouraged.)
๐œ‘    โ‡’   ๐œ‘
 
Theoremexbir 42525 Exportation implication also converting the consequent from a biconditional to an implication. Derived automatically from exbirVD 42900. (Contributed by Alan Sare, 31-Dec-2011.)
(((๐œ‘ โˆง ๐œ“) โ†’ (๐œ’ โ†” ๐œƒ)) โ†’ (๐œ‘ โ†’ (๐œ“ โ†’ (๐œƒ โ†’ ๐œ’))))
 
Theorem3impexpbicom 42526 Version of 3impexp 1359 where in addition the consequent is commuted. (Contributed by Alan Sare, 31-Dec-2011.)
(((๐œ‘ โˆง ๐œ“ โˆง ๐œ’) โ†’ (๐œƒ โ†” ๐œ)) โ†” (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ (๐œ โ†” ๐œƒ)))))
 
Theorem3impexpbicomi 42527 Inference associated with 3impexpbicom 42526. Derived automatically from 3impexpbicomiVD 42905. (Contributed by Alan Sare, 31-Dec-2011.)
((๐œ‘ โˆง ๐œ“ โˆง ๐œ’) โ†’ (๐œƒ โ†” ๐œ))    โ‡’   (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ (๐œ โ†” ๐œƒ))))
 
21.37.2  Supplementary unification deductions
 
Theorembi1imp 42528 Importation inference similar to imp 408, except the outermost implication of the hypothesis is a biconditional. (Contributed by Alan Sare, 6-Nov-2017.)
(๐œ‘ โ†” (๐œ“ โ†’ ๐œ’))    โ‡’   ((๐œ‘ โˆง ๐œ“) โ†’ ๐œ’)
 
Theorembi2imp 42529 Importation inference similar to imp 408, except both implications of the hypothesis are biconditionals. (Contributed by Alan Sare, 6-Nov-2017.)
(๐œ‘ โ†” (๐œ“ โ†” ๐œ’))    โ‡’   ((๐œ‘ โˆง ๐œ“) โ†’ ๐œ’)
 
Theorembi3impb 42530 Similar to 3impb 1116 with implication in hypothesis replaced by biconditional. (Contributed by Alan Sare, 6-Nov-2017.)
((๐œ‘ โˆง (๐œ“ โˆง ๐œ’)) โ†” ๐œƒ)    โ‡’   ((๐œ‘ โˆง ๐œ“ โˆง ๐œ’) โ†’ ๐œƒ)
 
Theorembi3impa 42531 Similar to 3impa 1111 with implication in hypothesis replaced by biconditional. (Contributed by Alan Sare, 6-Nov-2017.)
(((๐œ‘ โˆง ๐œ“) โˆง ๐œ’) โ†” ๐œƒ)    โ‡’   ((๐œ‘ โˆง ๐œ“ โˆง ๐œ’) โ†’ ๐œƒ)
 
Theorembi23impib 42532 3impib 1117 with the inner implication of the hypothesis a biconditional. (Contributed by Alan Sare, 6-Nov-2017.)
(๐œ‘ โ†’ ((๐œ“ โˆง ๐œ’) โ†” ๐œƒ))    โ‡’   ((๐œ‘ โˆง ๐œ“ โˆง ๐œ’) โ†’ ๐œƒ)
 
Theorembi13impib 42533 3impib 1117 with the outer implication of the hypothesis a biconditional. (Contributed by Alan Sare, 6-Nov-2017.)
(๐œ‘ โ†” ((๐œ“ โˆง ๐œ’) โ†’ ๐œƒ))    โ‡’   ((๐œ‘ โˆง ๐œ“ โˆง ๐œ’) โ†’ ๐œƒ)
 
Theorembi123impib 42534 3impib 1117 with the implications of the hypothesis biconditionals. (Contributed by Alan Sare, 6-Nov-2017.)
(๐œ‘ โ†” ((๐œ“ โˆง ๐œ’) โ†” ๐œƒ))    โ‡’   ((๐œ‘ โˆง ๐œ“ โˆง ๐œ’) โ†’ ๐œƒ)
 
Theorembi13impia 42535 3impia 1118 with the outer implication of the hypothesis a biconditional. (Contributed by Alan Sare, 6-Nov-2017.)
((๐œ‘ โˆง ๐œ“) โ†” (๐œ’ โ†’ ๐œƒ))    โ‡’   ((๐œ‘ โˆง ๐œ“ โˆง ๐œ’) โ†’ ๐œƒ)
 
Theorembi123impia 42536 3impia 1118 with the implications of the hypothesis biconditionals. (Contributed by Alan Sare, 6-Nov-2017.)
((๐œ‘ โˆง ๐œ“) โ†” (๐œ’ โ†” ๐œƒ))    โ‡’   ((๐œ‘ โˆง ๐œ“ โˆง ๐œ’) โ†’ ๐œƒ)
 
Theorembi33imp12 42537 3imp 1112 with innermost implication of the hypothesis a biconditional. (Contributed by Alan Sare, 6-Nov-2017.)
(๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†” ๐œƒ)))    โ‡’   ((๐œ‘ โˆง ๐œ“ โˆง ๐œ’) โ†’ ๐œƒ)
 
Theorembi23imp13 42538 3imp 1112 with middle implication of the hypothesis a biconditional. (Contributed by Alan Sare, 6-Nov-2017.)
(๐œ‘ โ†’ (๐œ“ โ†” (๐œ’ โ†’ ๐œƒ)))    โ‡’   ((๐œ‘ โˆง ๐œ“ โˆง ๐œ’) โ†’ ๐œƒ)
 
Theorembi13imp23 42539 3imp 1112 with outermost implication of the hypothesis a biconditional. (Contributed by Alan Sare, 6-Nov-2017.)
(๐œ‘ โ†” (๐œ“ โ†’ (๐œ’ โ†’ ๐œƒ)))    โ‡’   ((๐œ‘ โˆง ๐œ“ โˆง ๐œ’) โ†’ ๐œƒ)
 
Theorembi13imp2 42540 Similar to 3imp 1112 except the outermost and innermost implications are biconditionals. (Contributed by Alan Sare, 6-Nov-2017.)
(๐œ‘ โ†” (๐œ“ โ†’ (๐œ’ โ†” ๐œƒ)))    โ‡’   ((๐œ‘ โˆง ๐œ“ โˆง ๐œ’) โ†’ ๐œƒ)
 
Theorembi12imp3 42541 Similar to 3imp 1112 except all but innermost implication are biconditionals. (Contributed by Alan Sare, 6-Nov-2017.)
(๐œ‘ โ†” (๐œ“ โ†” (๐œ’ โ†’ ๐œƒ)))    โ‡’   ((๐œ‘ โˆง ๐œ“ โˆง ๐œ’) โ†’ ๐œƒ)
 
Theorembi23imp1 42542 Similar to 3imp 1112 except all but outermost implication are biconditionals. (Contributed by Alan Sare, 6-Nov-2017.)
(๐œ‘ โ†’ (๐œ“ โ†” (๐œ’ โ†” ๐œƒ)))    โ‡’   ((๐œ‘ โˆง ๐œ“ โˆง ๐œ’) โ†’ ๐œƒ)
 
Theorembi123imp0 42543 Similar to 3imp 1112 except all implications are biconditionals. (Contributed by Alan Sare, 6-Nov-2017.)
(๐œ‘ โ†” (๐œ“ โ†” (๐œ’ โ†” ๐œƒ)))    โ‡’   ((๐œ‘ โˆง ๐œ“ โˆง ๐œ’) โ†’ ๐œƒ)
 
Theorem4animp1 42544 A single hypothesis unification deduction with an assertion which is an implication with a 4-right-nested conjunction antecedent. (Contributed by Alan Sare, 30-May-2018.)
((๐œ‘ โˆง ๐œ“ โˆง ๐œ’) โ†’ (๐œ โ†” ๐œƒ))    โ‡’   ((((๐œ‘ โˆง ๐œ“) โˆง ๐œ’) โˆง ๐œƒ) โ†’ ๐œ)
 
Theorem4an31 42545 A rearrangement of conjuncts for a 4-right-nested conjunction. (Contributed by Alan Sare, 30-May-2018.)
((((๐œ’ โˆง ๐œ“) โˆง ๐œ‘) โˆง ๐œƒ) โ†’ ๐œ)    โ‡’   ((((๐œ‘ โˆง ๐œ“) โˆง ๐œ’) โˆง ๐œƒ) โ†’ ๐œ)
 
Theorem4an4132 42546 A rearrangement of conjuncts for a 4-right-nested conjunction. (Contributed by Alan Sare, 30-May-2018.)
((((๐œƒ โˆง ๐œ’) โˆง ๐œ“) โˆง ๐œ‘) โ†’ ๐œ)    โ‡’   ((((๐œ‘ โˆง ๐œ“) โˆง ๐œ’) โˆง ๐œƒ) โ†’ ๐œ)
 
Theoremexpcomdg 42547 Biconditional form of expcomd 418. (Contributed by Alan Sare, 22-Jul-2012.) (New usage is discouraged.)
((๐œ‘ โ†’ ((๐œ“ โˆง ๐œ’) โ†’ ๐œƒ)) โ†” (๐œ‘ โ†’ (๐œ’ โ†’ (๐œ“ โ†’ ๐œƒ))))
 
21.37.3  Conventional Metamath proofs, some derived from VD proofs
 
Theoremiidn3 42548 idn3 42662 without virtual deduction connectives. Special theorem needed for the Virtual Deduction translation tool. (Contributed by Alan Sare, 23-Jul-2011.) (Proof modification is discouraged.) (New usage is discouraged.)
(๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ ๐œ’)))
 
Theoremee222 42549 e222 42683 without virtual deduction connectives. Special theorem needed for the Virtual Deduction translation tool. (Contributed by Alan Sare, 7-Jul-2011.) (Proof modification is discouraged.) (New usage is discouraged.)
(๐œ‘ โ†’ (๐œ“ โ†’ ๐œ’))    &   (๐œ‘ โ†’ (๐œ“ โ†’ ๐œƒ))    &   (๐œ‘ โ†’ (๐œ“ โ†’ ๐œ))    &   (๐œ’ โ†’ (๐œƒ โ†’ (๐œ โ†’ ๐œ‚)))    โ‡’   (๐œ‘ โ†’ (๐œ“ โ†’ ๐œ‚))
 
Theoremee3bir 42550 Right-biconditional form of e3 42784 without virtual deduction connectives. Special theorem needed for the Virtual Deduction translation tool. (Contributed by Alan Sare, 22-Jul-2011.) (Proof modification is discouraged.) (New usage is discouraged.)
(๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ ๐œƒ)))    &   (๐œ โ†” ๐œƒ)    โ‡’   (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ ๐œ)))
 
Theoremee13 42551 e13 42795 without virtual deduction connectives. Special theorem needed for the Virtual Deduction translation tool. (Contributed by Alan Sare, 28-Oct-2011.) (Proof modification is discouraged.) (New usage is discouraged.)
(๐œ‘ โ†’ ๐œ“)    &   (๐œ‘ โ†’ (๐œ’ โ†’ (๐œƒ โ†’ ๐œ)))    &   (๐œ“ โ†’ (๐œ โ†’ ๐œ‚))    โ‡’   (๐œ‘ โ†’ (๐œ’ โ†’ (๐œƒ โ†’ ๐œ‚)))
 
Theoremee121 42552 e121 42703 without virtual deductions. (Contributed by Alan Sare, 13-Jul-2011.) (Proof modification is discouraged.) (New usage is discouraged.)
(๐œ‘ โ†’ ๐œ“)    &   (๐œ‘ โ†’ (๐œ’ โ†’ ๐œƒ))    &   (๐œ‘ โ†’ ๐œ)    &   (๐œ“ โ†’ (๐œƒ โ†’ (๐œ โ†’ ๐œ‚)))    โ‡’   (๐œ‘ โ†’ (๐œ’ โ†’ ๐œ‚))
 
Theoremee122 42553 e122 42700 without virtual deductions. (Contributed by Alan Sare, 13-Jul-2011.) (Proof modification is discouraged.) (New usage is discouraged.)
(๐œ‘ โ†’ ๐œ“)    &   (๐œ‘ โ†’ (๐œ’ โ†’ ๐œƒ))    &   (๐œ‘ โ†’ (๐œ’ โ†’ ๐œ))    &   (๐œ“ โ†’ (๐œƒ โ†’ (๐œ โ†’ ๐œ‚)))    โ‡’   (๐œ‘ โ†’ (๐œ’ โ†’ ๐œ‚))
 
Theoremee333 42554 e333 42780 without virtual deductions. (Contributed by Alan Sare, 17-Jul-2011.) (Proof modification is discouraged.) (New usage is discouraged.)
(๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ ๐œƒ)))    &   (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ ๐œ)))    &   (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ ๐œ‚)))    &   (๐œƒ โ†’ (๐œ โ†’ (๐œ‚ โ†’ ๐œ)))    โ‡’   (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ ๐œ)))
 
Theoremee323 42555 e323 42813 without virtual deductions. (Contributed by Alan Sare, 17-Apr-2012.) (Proof modification is discouraged.) (New usage is discouraged.)
(๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ ๐œƒ)))    &   (๐œ‘ โ†’ (๐œ“ โ†’ ๐œ))    &   (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ ๐œ‚)))    &   (๐œƒ โ†’ (๐œ โ†’ (๐œ‚ โ†’ ๐œ)))    โ‡’   (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ ๐œ)))
 
Theorem3ornot23 42556 If the second and third disjuncts of a true triple disjunction are false, then the first disjunct is true. Automatically derived from 3ornot23VD 42894. (Contributed by Alan Sare, 31-Dec-2011.) (Proof modification is discouraged.) (New usage is discouraged.)
((ยฌ ๐œ‘ โˆง ยฌ ๐œ“) โ†’ ((๐œ’ โˆจ ๐œ‘ โˆจ ๐œ“) โ†’ ๐œ’))
 
Theoremorbi1r 42557 orbi1 917 with order of disjuncts reversed. Derived from orbi1rVD 42895. (Contributed by Alan Sare, 31-Dec-2011.) (Proof modification is discouraged.) (New usage is discouraged.)
((๐œ‘ โ†” ๐œ“) โ†’ ((๐œ’ โˆจ ๐œ‘) โ†” (๐œ’ โˆจ ๐œ“)))
 
Theorem3orbi123 42558 pm4.39 976 with a 3-conjunct antecedent. This proof is 3orbi123VD 42897 automatically translated and minimized. (Contributed by Alan Sare, 31-Dec-2011.) (Proof modification is discouraged.) (New usage is discouraged.)
(((๐œ‘ โ†” ๐œ“) โˆง (๐œ’ โ†” ๐œƒ) โˆง (๐œ โ†” ๐œ‚)) โ†’ ((๐œ‘ โˆจ ๐œ’ โˆจ ๐œ) โ†” (๐œ“ โˆจ ๐œƒ โˆจ ๐œ‚)))
 
Theoremsyl5imp 42559 Closed form of syl5 34. Derived automatically from syl5impVD 42910. (Contributed by Alan Sare, 31-Dec-2011.) (Proof modification is discouraged.) (New usage is discouraged.)
((๐œ‘ โ†’ (๐œ“ โ†’ ๐œ’)) โ†’ ((๐œƒ โ†’ ๐œ“) โ†’ (๐œ‘ โ†’ (๐œƒ โ†’ ๐œ’))))
 
Theoremimpexpd 42560 The following User's Proof is a Virtual Deduction proof completed automatically by the tools program completeusersproof.cmd, which invokes Mel L. O'Cat's mmj2 and Norm Megill's Metamath Proof Assistant. After the User's Proof was completed, it was minimized. The completed User's Proof before minimization is not shown. (Contributed by Alan Sare, 18-Mar-2012.) (Proof modification is discouraged.) (New usage is discouraged.)
1:: (((๐œ“ โˆง ๐œ’) โ†’ ๐œƒ) โ†” (๐œ“ โ†’ (๐œ’ โ†’ ๐œƒ)))
qed:1: ((๐œ‘ โ†’ ((๐œ“ โˆง ๐œ’) โ†’ ๐œƒ)) โ†” (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ ๐œƒ))))
((๐œ‘ โ†’ ((๐œ“ โˆง ๐œ’) โ†’ ๐œƒ)) โ†” (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ ๐œƒ))))
 
Theoremcom3rgbi 42561 The following User's Proof is a Virtual Deduction proof completed automatically by the tools program completeusersproof.cmd, which invokes Mel L. O'Cat's mmj2 and Norm Megill's Metamath Proof Assistant. The completed Virtual Deduction Proof (not shown) was minimized. The minimized proof is shown. (Contributed by Alan Sare, 18-Mar-2012.) (Proof modification is discouraged.) (New usage is discouraged.)
1:: ((๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ ๐œƒ))) โ†’ (๐œ‘ โ†’ (๐œ’ โ†’ (๐œ“ โ†’ ๐œƒ))))
2:: ((๐œ‘ โ†’ (๐œ’ โ†’ (๐œ“ โ†’ ๐œƒ))) โ†’ (๐œ’ โ†’ (๐œ‘ โ†’ (๐œ“ โ†’ ๐œƒ))))
3:1,2: ((๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ ๐œƒ))) โ†’ (๐œ’ โ†’ (๐œ‘ โ†’ (๐œ“ โ†’ ๐œƒ))))
4:: ((๐œ’ โ†’ (๐œ‘ โ†’ (๐œ“ โ†’ ๐œƒ))) โ†’ (๐œ‘ โ†’ (๐œ’ โ†’ (๐œ“ โ†’ ๐œƒ))))
5:: ((๐œ‘ โ†’ (๐œ’ โ†’ (๐œ“ โ†’ ๐œƒ))) โ†’ (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ ๐œƒ))))
6:4,5: ((๐œ’ โ†’ (๐œ‘ โ†’ (๐œ“ โ†’ ๐œƒ))) โ†’ (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ ๐œƒ))))
qed:3,6: ((๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ ๐œƒ))) โ†” (๐œ’ โ†’ (๐œ‘ โ†’ (๐œ“ โ†’ ๐œƒ))))
((๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ ๐œƒ))) โ†” (๐œ’ โ†’ (๐œ‘ โ†’ (๐œ“ โ†’ ๐œƒ))))
 
Theoremimpexpdcom 42562 The following User's Proof is a Virtual Deduction proof completed automatically by the tools program completeusersproof.cmd, which invokes Mel L. O'Cat's mmj2 and Norm Megill's Metamath Proof Assistant. The completed Virtual Deduction Proof (not shown) was minimized. The minimized proof is shown. (Contributed by Alan Sare, 18-Mar-2012.) (Proof modification is discouraged.) (New usage is discouraged.)
1:: ((๐œ‘ โ†’ ((๐œ“ โˆง ๐œ’) โ†’ ๐œƒ)) โ†” (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ ๐œƒ))))
2:: ((๐œ“ โ†’ (๐œ’ โ†’ (๐œ‘ โ†’ ๐œƒ))) โ†” (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ ๐œƒ))))
qed:1,2: ((๐œ‘ โ†’ ((๐œ“ โˆง ๐œ’) โ†’ ๐œƒ)) โ†” (๐œ“ โ†’ (๐œ’ โ†’ (๐œ‘ โ†’ ๐œƒ))))
((๐œ‘ โ†’ ((๐œ“ โˆง ๐œ’) โ†’ ๐œƒ)) โ†” (๐œ“ โ†’ (๐œ’ โ†’ (๐œ‘ โ†’ ๐œƒ))))
 
Theoremee1111 42563 Non-virtual deduction form of e1111 42722. (Contributed by Alan Sare, 18-Mar-2012.) (Proof modification is discouraged.) (New usage is discouraged.) The following User's Proof is a Virtual Deduction proof completed automatically by the tools program completeusersproof.cmd, which invokes Mel L. O'Cat's mmj2 and Norm Megill's Metamath Proof Assistant. The completed Virtual Deduction Proof (not shown) was minimized. The minimized proof is shown.
h1:: (๐œ‘ โ†’ ๐œ“)
h2:: (๐œ‘ โ†’ ๐œ’)
h3:: (๐œ‘ โ†’ ๐œƒ)
h4:: (๐œ‘ โ†’ ๐œ)
h5:: (๐œ“ โ†’ (๐œ’ โ†’ (๐œƒ โ†’ (๐œ โ†’ ๐œ‚))))
6:1,5: (๐œ‘ โ†’ (๐œ’ โ†’ (๐œƒ โ†’ (๐œ โ†’ ๐œ‚))))
7:6: (๐œ’ โ†’ (๐œ‘ โ†’ (๐œƒ โ†’ (๐œ โ†’ ๐œ‚))))
8:2,7: (๐œ‘ โ†’ (๐œ‘ โ†’ (๐œƒ โ†’ (๐œ โ†’ ๐œ‚))))
9:8: (๐œ‘ โ†’ (๐œƒ โ†’ (๐œ โ†’ ๐œ‚)))
10:9: (๐œƒ โ†’ (๐œ‘ โ†’ (๐œ โ†’ ๐œ‚)))
11:3,10: (๐œ‘ โ†’ (๐œ‘ โ†’ (๐œ โ†’ ๐œ‚)))
12:11: (๐œ‘ โ†’ (๐œ โ†’ ๐œ‚))
13:12: (๐œ โ†’ (๐œ‘ โ†’ ๐œ‚))
14:4,13: (๐œ‘ โ†’ (๐œ‘ โ†’ ๐œ‚))
qed:14: (๐œ‘ โ†’ ๐œ‚)
(๐œ‘ โ†’ ๐œ“)    &   (๐œ‘ โ†’ ๐œ’)    &   (๐œ‘ โ†’ ๐œƒ)    &   (๐œ‘ โ†’ ๐œ)    &   (๐œ“ โ†’ (๐œ’ โ†’ (๐œƒ โ†’ (๐œ โ†’ ๐œ‚))))    โ‡’   (๐œ‘ โ†’ ๐œ‚)
 
Theorempm2.43bgbi 42564 Logical equivalence of a 2-left-nested implication and a 1-left-nested implicated when two antecedents of the former implication are identical. (Contributed by Alan Sare, 18-Mar-2012.) (Proof modification is discouraged.) (New usage is discouraged.) The following User's Proof is a Virtual Deduction proof completed automatically by the tools program completeusersproof.cmd, which invokes Mel L. O'Cat's mmj2 and Norm Megill's Metamath Proof Assistant. The completed Virtual Deduction Proof (not shown) was minimized. The minimized proof is shown.
1:: ((๐œ‘ โ†’ (๐œ“ โ†’ (๐œ‘ โ†’ ๐œ’))) โ†’ (๐œ‘ โ†’ (๐œ‘ โ†’ (๐œ“ โ†’ ๐œ’))))
2:: ((๐œ‘ โ†’ (๐œ‘ โ†’ (๐œ“ โ†’ ๐œ’))) โ†’ (๐œ‘ โ†’ (๐œ“ โ†’ ๐œ’)))
3:1,2: ((๐œ‘ โ†’ (๐œ“ โ†’ (๐œ‘ โ†’ ๐œ’))) โ†’ (๐œ‘ โ†’ (๐œ“ โ†’ ๐œ’)))
4:: ((๐œ‘ โ†’ (๐œ“ โ†’ ๐œ’)) โ†’ (๐œ“ โ†’ (๐œ‘ โ†’ ๐œ’)))
5:3,4: ((๐œ‘ โ†’ (๐œ“ โ†’ (๐œ‘ โ†’ ๐œ’))) โ†’ (๐œ“ โ†’ (๐œ‘ โ†’ ๐œ’)))
6:: ((๐œ“ โ†’ (๐œ‘ โ†’ ๐œ’)) โ†’ (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ‘ โ†’ ๐œ’))))
qed:5,6: ((๐œ‘ โ†’ (๐œ“ โ†’ (๐œ‘ โ†’ ๐œ’))) โ†” (๐œ“ โ†’ (๐œ‘ โ†’ ๐œ’)))
((๐œ‘ โ†’ (๐œ“ โ†’ (๐œ‘ โ†’ ๐œ’))) โ†” (๐œ“ โ†’ (๐œ‘ โ†’ ๐œ’)))
 
Theorempm2.43cbi 42565 Logical equivalence of a 3-left-nested implication and a 2-left-nested implicated when two antecedents of the former implication are identical. (Contributed by Alan Sare, 18-Mar-2012.) (Proof modification is discouraged.) (New usage is discouraged.) The following User's Proof is a Virtual Deduction proof completed automatically by the tools program completeusersproof.cmd, which invokes Mel L. O'Cat's mmj2 and Norm Megill's Metamath Proof Assistant. The completed Virtual Deduction Proof (not shown) was minimized. The minimized proof is shown.
1:: ((๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ (๐œ‘ โ†’ ๐œƒ))) ) โ†’ (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ‘ โ†’ (๐œ’ โ†’ ๐œƒ)))))
2:: ((๐œ‘ โ†’ (๐œ“ โ†’ (๐œ‘ โ†’ (๐œ’ โ†’ ๐œƒ))) ) โ†’ (๐œ“ โ†’ (๐œ‘ โ†’ (๐œ’ โ†’ ๐œƒ))))
3:1,2: ((๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ (๐œ‘ โ†’ ๐œƒ))) ) โ†’ (๐œ“ โ†’ (๐œ‘ โ†’ (๐œ’ โ†’ ๐œƒ))))
4:: ((๐œ“ โ†’ (๐œ‘ โ†’ (๐œ’ โ†’ ๐œƒ))) โ†’ (๐œ“ โ†’ (๐œ’ โ†’ (๐œ‘ โ†’ ๐œƒ))))
5:3,4: ((๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ (๐œ‘ โ†’ ๐œƒ))) ) โ†’ (๐œ“ โ†’ (๐œ’ โ†’ (๐œ‘ โ†’ ๐œƒ))))
6:: ((๐œ“ โ†’ (๐œ’ โ†’ (๐œ‘ โ†’ ๐œƒ))) โ†’ (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ (๐œ‘ โ†’ ๐œƒ)))))
qed:5,6: ((๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ (๐œ‘ โ†’ ๐œƒ))) ) โ†” (๐œ“ โ†’ (๐œ’ โ†’ (๐œ‘ โ†’ ๐œƒ))))
((๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ (๐œ‘ โ†’ ๐œƒ)))) โ†” (๐œ“ โ†’ (๐œ’ โ†’ (๐œ‘ โ†’ ๐œƒ))))
 
Theoremee233 42566 Non-virtual deduction form of e233 42812. (Contributed by Alan Sare, 18-Mar-2012.) (Proof modification is discouraged.) (New usage is discouraged.) The following User's Proof is a Virtual Deduction proof completed automatically by the tools program completeusersproof.cmd, which invokes Mel L. O'Cat's mmj2 and Norm Megill's Metamath Proof Assistant. The completed Virtual Deduction Proof (not shown) was minimized. The minimized proof is shown.
h1:: (๐œ‘ โ†’ (๐œ“ โ†’ ๐œ’))
h2:: (๐œ‘ โ†’ (๐œ“ โ†’ (๐œƒ โ†’ ๐œ)))
h3:: (๐œ‘ โ†’ (๐œ“ โ†’ (๐œƒ โ†’ ๐œ‚)))
h4:: (๐œ’ โ†’ (๐œ โ†’ (๐œ‚ โ†’ ๐œ)))
5:1,4: (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ โ†’ (๐œ‚ โ†’ ๐œ))) )
6:5: (๐œ โ†’ (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ‚ โ†’ ๐œ))) )
7:2,6: (๐œ‘ โ†’ (๐œ“ โ†’ (๐œƒ โ†’ (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ‚ โ†’ ๐œ))))))
8:7: (๐œ“ โ†’ (๐œƒ โ†’ (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ‚ โ†’ ๐œ)))))
9:8: (๐œƒ โ†’ (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ‚ โ†’ ๐œ))) )
10:9: (๐œ‘ โ†’ (๐œ“ โ†’ (๐œƒ โ†’ (๐œ‚ โ†’ ๐œ))) )
11:10: (๐œ‚ โ†’ (๐œ‘ โ†’ (๐œ“ โ†’ (๐œƒ โ†’ ๐œ))) )
12:3,11: (๐œ‘ โ†’ (๐œ“ โ†’ (๐œƒ โ†’ (๐œ‘ โ†’ (๐œ“ โ†’ (๐œƒ โ†’ ๐œ))))))
13:12: (๐œ“ โ†’ (๐œƒ โ†’ (๐œ‘ โ†’ (๐œ“ โ†’ (๐œƒ โ†’ ๐œ)))))
14:13: (๐œƒ โ†’ (๐œ‘ โ†’ (๐œ“ โ†’ (๐œƒ โ†’ ๐œ))) )
qed:14: (๐œ‘ โ†’ (๐œ“ โ†’ (๐œƒ โ†’ ๐œ)))
(๐œ‘ โ†’ (๐œ“ โ†’ ๐œ’))    &   (๐œ‘ โ†’ (๐œ“ โ†’ (๐œƒ โ†’ ๐œ)))    &   (๐œ‘ โ†’ (๐œ“ โ†’ (๐œƒ โ†’ ๐œ‚)))    &   (๐œ’ โ†’ (๐œ โ†’ (๐œ‚ โ†’ ๐œ)))    โ‡’   (๐œ‘ โ†’ (๐œ“ โ†’ (๐œƒ โ†’ ๐œ)))
 
Theoremimbi13 42567 Join three logical equivalences to form equivalence of implications. imbi13 42567 is imbi13VD 42921 without virtual deductions and was automatically derived from imbi13VD 42921 using the tools program translate..without..overwriting.cmd and Metamath's minimize command. (Contributed by Alan Sare, 18-Mar-2012.) (Proof modification is discouraged.) (New usage is discouraged.)
((๐œ‘ โ†” ๐œ“) โ†’ ((๐œ’ โ†” ๐œƒ) โ†’ ((๐œ โ†” ๐œ‚) โ†’ ((๐œ‘ โ†’ (๐œ’ โ†’ ๐œ)) โ†” (๐œ“ โ†’ (๐œƒ โ†’ ๐œ‚))))))
 
Theoremee33 42568 Non-virtual deduction form of e33 42781. (Contributed by Alan Sare, 18-Mar-2012.) (Proof modification is discouraged.) (New usage is discouraged.) The following User's Proof is a Virtual Deduction proof completed automatically by the tools program completeusersproof.cmd, which invokes Mel L. O'Cat's mmj2 and Norm Megill's Metamath Proof Assistant. The completed Virtual Deduction Proof (not shown) was minimized. The minimized proof is shown.
h1:: (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ ๐œƒ)))
h2:: (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ ๐œ)))
h3:: (๐œƒ โ†’ (๐œ โ†’ ๐œ‚))
4:1,3: (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ (๐œ โ†’ ๐œ‚))))
5:4: (๐œ โ†’ (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ ๐œ‚))))
6:2,5: (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ ๐œ‚))))))
7:6: (๐œ“ โ†’ (๐œ’ โ†’ (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ ๐œ‚)))))
8:7: (๐œ’ โ†’ (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ ๐œ‚))))
qed:8: (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ ๐œ‚)))
(๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ ๐œƒ)))    &   (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ ๐œ)))    &   (๐œƒ โ†’ (๐œ โ†’ ๐œ‚))    โ‡’   (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ ๐œ‚)))
 
Theoremcon5 42569 Biconditional contraposition variation. This proof is con5VD 42947 automatically translated and minimized. (Contributed by Alan Sare, 21-Apr-2013.) (Proof modification is discouraged.) (New usage is discouraged.)
((๐œ‘ โ†” ยฌ ๐œ“) โ†’ (ยฌ ๐œ‘ โ†’ ๐œ“))
 
Theoremcon5i 42570 Inference form of con5 42569. (Contributed by Alan Sare, 21-Apr-2013.) (Proof modification is discouraged.) (New usage is discouraged.)
(๐œ‘ โ†” ยฌ ๐œ“)    โ‡’   (ยฌ ๐œ‘ โ†’ ๐œ“)
 
Theoremexlimexi 42571 Inference similar to Theorem 19.23 of [Margaris] p. 90. (Contributed by Alan Sare, 21-Apr-2013.) (Proof modification is discouraged.) (New usage is discouraged.)
(๐œ“ โ†’ โˆ€๐‘ฅ๐œ“)    &   (โˆƒ๐‘ฅ๐œ‘ โ†’ (๐œ‘ โ†’ ๐œ“))    โ‡’   (โˆƒ๐‘ฅ๐œ‘ โ†’ ๐œ“)
 
Theoremsb5ALT 42572* Equivalence for substitution. Alternate proof of sb5 2269. This proof is sb5ALTVD 42960 automatically translated and minimized. (Contributed by Alan Sare, 21-Apr-2013.) (Proof modification is discouraged.) (New usage is discouraged.)
([๐‘ฆ / ๐‘ฅ]๐œ‘ โ†” โˆƒ๐‘ฅ(๐‘ฅ = ๐‘ฆ โˆง ๐œ‘))
 
Theoremeexinst01 42573 exinst01 42672 without virtual deductions. (Contributed by Alan Sare, 21-Apr-2013.) (Proof modification is discouraged.) (New usage is discouraged.)
โˆƒ๐‘ฅ๐œ“    &   (๐œ‘ โ†’ (๐œ“ โ†’ ๐œ’))    &   (๐œ‘ โ†’ โˆ€๐‘ฅ๐œ‘)    &   (๐œ’ โ†’ โˆ€๐‘ฅ๐œ’)    โ‡’   (๐œ‘ โ†’ ๐œ’)
 
Theoremeexinst11 42574 exinst11 42673 without virtual deductions. (Contributed by Alan Sare, 21-Apr-2013.) (Proof modification is discouraged.) (New usage is discouraged.)
(๐œ‘ โ†’ โˆƒ๐‘ฅ๐œ“)    &   (๐œ‘ โ†’ (๐œ“ โ†’ ๐œ’))    &   (๐œ‘ โ†’ โˆ€๐‘ฅ๐œ‘)    &   (๐œ’ โ†’ โˆ€๐‘ฅ๐œ’)    โ‡’   (๐œ‘ โ†’ ๐œ’)
 
Theoremvk15.4j 42575 Excercise 4j of Unit 15 of "Understanding Symbolic Logic", Fifth Edition (2008), by Virginia Klenk. This proof is the minimized Hilbert-style axiomatic version of the Fitch-style Natural Deduction proof found on page 442 of Klenk and was automatically derived from that proof. vk15.4j 42575 is vk15.4jVD 42961 automatically translated and minimized. (Contributed by Alan Sare, 21-Apr-2013.) (Proof modification is discouraged.) (New usage is discouraged.)
ยฌ (โˆƒ๐‘ฅ ยฌ ๐œ‘ โˆง โˆƒ๐‘ฅ(๐œ“ โˆง ยฌ ๐œ’))    &   (โˆ€๐‘ฅ๐œ’ โ†’ ยฌ โˆƒ๐‘ฅ(๐œƒ โˆง ๐œ))    &    ยฌ โˆ€๐‘ฅ(๐œ โ†’ ๐œ‘)    โ‡’   (ยฌ โˆƒ๐‘ฅ ยฌ ๐œƒ โ†’ ยฌ โˆ€๐‘ฅ๐œ“)
 
TheoremnotnotrALT 42576 Converse of double negation. Alternate proof of notnotr 130. This proof is notnotrALTVD 42962 automatically translated and minimized. (Contributed by Alan Sare, 21-Apr-2013.) (Proof modification is discouraged.) (New usage is discouraged.)
(ยฌ ยฌ ๐œ‘ โ†’ ๐œ‘)
 
Theoremcon3ALT2 42577 Contraposition. Alternate proof of con3 153. This proof is con3ALTVD 42963 automatically translated and minimized. (Contributed by Alan Sare, 21-Apr-2013.) (Proof modification is discouraged.) (New usage is discouraged.)
((๐œ‘ โ†’ ๐œ“) โ†’ (ยฌ ๐œ“ โ†’ ยฌ ๐œ‘))
 
Theoremssralv2 42578* Quantification restricted to a subclass for two quantifiers. ssralv 4009 for two quantifiers. The proof of ssralv2 42578 was automatically generated by minimizing the automatically translated proof of ssralv2VD 42913. The automatic translation is by the tools program translate_without_overwriting.cmd. (Contributed by Alan Sare, 18-Feb-2012.) (Proof modification is discouraged.) (New usage is discouraged.)
((๐ด โŠ† ๐ต โˆง ๐ถ โŠ† ๐ท) โ†’ (โˆ€๐‘ฅ โˆˆ ๐ต โˆ€๐‘ฆ โˆˆ ๐ท ๐œ‘ โ†’ โˆ€๐‘ฅ โˆˆ ๐ด โˆ€๐‘ฆ โˆˆ ๐ถ ๐œ‘))
 
Theoremsbc3or 42579 sbcor 3791 with a 3-disjuncts. This proof is sbc3orgVD 42898 automatically translated and minimized. (Contributed by Alan Sare, 31-Dec-2011.) (Revised by NM, 24-Aug-2018.) (Proof modification is discouraged.) (New usage is discouraged.)
([๐ด / ๐‘ฅ](๐œ‘ โˆจ ๐œ“ โˆจ ๐œ’) โ†” ([๐ด / ๐‘ฅ]๐œ‘ โˆจ [๐ด / ๐‘ฅ]๐œ“ โˆจ [๐ด / ๐‘ฅ]๐œ’))
 
Theoremalrim3con13v 42580* Closed form of alrimi 2207 with 2 additional conjuncts having no occurrences of the quantifying variable. This proof is 19.21a3con13vVD 42899 automatically translated and minimized. (Contributed by Alan Sare, 31-Dec-2011.) (Proof modification is discouraged.) (New usage is discouraged.)
((๐œ‘ โ†’ โˆ€๐‘ฅ๐œ‘) โ†’ ((๐œ“ โˆง ๐œ‘ โˆง ๐œ’) โ†’ โˆ€๐‘ฅ(๐œ“ โˆง ๐œ‘ โˆง ๐œ’)))
 
Theoremrspsbc2 42581* rspsbc 3834 with two quantifying variables. This proof is rspsbc2VD 42902 automatically translated and minimized. (Contributed by Alan Sare, 31-Dec-2011.) (Proof modification is discouraged.) (New usage is discouraged.)
(๐ด โˆˆ ๐ต โ†’ (๐ถ โˆˆ ๐ท โ†’ (โˆ€๐‘ฅ โˆˆ ๐ต โˆ€๐‘ฆ โˆˆ ๐ท ๐œ‘ โ†’ [๐ถ / ๐‘ฆ][๐ด / ๐‘ฅ]๐œ‘)))
 
Theoremsbcoreleleq 42582* Substitution of a setvar variable for another setvar variable in a 3-conjunct formula. Derived automatically from sbcoreleleqVD 42906. (Contributed by Alan Sare, 31-Dec-2011.) (Proof modification is discouraged.) (New usage is discouraged.)
(๐ด โˆˆ ๐‘‰ โ†’ ([๐ด / ๐‘ฆ](๐‘ฅ โˆˆ ๐‘ฆ โˆจ ๐‘ฆ โˆˆ ๐‘ฅ โˆจ ๐‘ฅ = ๐‘ฆ) โ†” (๐‘ฅ โˆˆ ๐ด โˆจ ๐ด โˆˆ ๐‘ฅ โˆจ ๐‘ฅ = ๐ด)))
 
Theoremtratrb 42583* If a class is transitive and any two distinct elements of the class are E-comparable, then every element of that class is transitive. Derived automatically from tratrbVD 42908. (Contributed by Alan Sare, 31-Dec-2011.) (Proof modification is discouraged.) (New usage is discouraged.)
((Tr ๐ด โˆง โˆ€๐‘ฅ โˆˆ ๐ด โˆ€๐‘ฆ โˆˆ ๐ด (๐‘ฅ โˆˆ ๐‘ฆ โˆจ ๐‘ฆ โˆˆ ๐‘ฅ โˆจ ๐‘ฅ = ๐‘ฆ) โˆง ๐ต โˆˆ ๐ด) โ†’ Tr ๐ต)
 
TheoremordelordALT 42584 An element of an ordinal class is ordinal. Proposition 7.6 of [TakeutiZaring] p. 36. This is an alternate proof of ordelord 6336 using the Axiom of Regularity indirectly through dford2 9490. dford2 is a weaker definition of ordinal number. Given the Axiom of Regularity, it need not be assumed that E Fr ๐ด because this is inferred by the Axiom of Regularity. ordelordALT 42584 is ordelordALTVD 42914 without virtual deductions and was automatically derived from ordelordALTVD 42914 using the tools program translate..without..overwriting.cmd and Metamath's minimize command. (Contributed by Alan Sare, 18-Feb-2012.) (Proof modification is discouraged.) (New usage is discouraged.)
((Ord ๐ด โˆง ๐ต โˆˆ ๐ด) โ†’ Ord ๐ต)
 
Theoremsbcim2g 42585 Distribution of class substitution over a left-nested implication. Similar to sbcimg 3789. sbcim2g 42585 is sbcim2gVD 42922 without virtual deductions and was automatically derived from sbcim2gVD 42922 using the tools program translate..without..overwriting.cmd and Metamath's minimize command. (Contributed by Alan Sare, 18-Mar-2012.) (Proof modification is discouraged.) (New usage is discouraged.)
(๐ด โˆˆ ๐‘‰ โ†’ ([๐ด / ๐‘ฅ](๐œ‘ โ†’ (๐œ“ โ†’ ๐œ’)) โ†” ([๐ด / ๐‘ฅ]๐œ‘ โ†’ ([๐ด / ๐‘ฅ]๐œ“ โ†’ [๐ด / ๐‘ฅ]๐œ’))))
 
Theoremsbcbi 42586 Implication form of sbcbii 3798. sbcbi 42586 is sbcbiVD 42923 without virtual deductions and was automatically derived from sbcbiVD 42923 using the tools program translate..without..overwriting.cmd and Metamath's minimize command. (Contributed by Alan Sare, 18-Mar-2012.) (Proof modification is discouraged.) (New usage is discouraged.)
(๐ด โˆˆ ๐‘‰ โ†’ (โˆ€๐‘ฅ(๐œ‘ โ†” ๐œ“) โ†’ ([๐ด / ๐‘ฅ]๐œ‘ โ†” [๐ด / ๐‘ฅ]๐œ“)))
 
Theoremtrsbc 42587* Formula-building inference rule for class substitution, substituting a class variable for the setvar variable of the transitivity predicate. trsbc 42587 is trsbcVD 42924 without virtual deductions and was automatically derived from trsbcVD 42924 using the tools program translate..without..overwriting.cmd and Metamath's minimize command. (Contributed by Alan Sare, 18-Mar-2012.) (Proof modification is discouraged.) (New usage is discouraged.)
(๐ด โˆˆ ๐‘‰ โ†’ ([๐ด / ๐‘ฅ]Tr ๐‘ฅ โ†” Tr ๐ด))
 
TheoremtruniALT 42588* The union of a class of transitive sets is transitive. Alternate proof of truni 5237. truniALT 42588 is truniALTVD 42925 without virtual deductions and was automatically derived from truniALTVD 42925 using the tools program translate..without..overwriting.cmd and Metamath's minimize command. (Contributed by Alan Sare, 18-Mar-2012.) (Proof modification is discouraged.) (New usage is discouraged.)
(โˆ€๐‘ฅ โˆˆ ๐ด Tr ๐‘ฅ โ†’ Tr โˆช ๐ด)
 
TheoremonfrALTlem5 42589* Lemma for onfrALT 42596. (Contributed by Alan Sare, 22-Jul-2012.) (Proof modification is discouraged.) (New usage is discouraged.)
([(๐‘Ž โˆฉ ๐‘ฅ) / ๐‘]((๐‘ โŠ† (๐‘Ž โˆฉ ๐‘ฅ) โˆง ๐‘ โ‰  โˆ…) โ†’ โˆƒ๐‘ฆ โˆˆ ๐‘ (๐‘ โˆฉ ๐‘ฆ) = โˆ…) โ†” (((๐‘Ž โˆฉ ๐‘ฅ) โŠ† (๐‘Ž โˆฉ ๐‘ฅ) โˆง (๐‘Ž โˆฉ ๐‘ฅ) โ‰  โˆ…) โ†’ โˆƒ๐‘ฆ โˆˆ (๐‘Ž โˆฉ ๐‘ฅ)((๐‘Ž โˆฉ ๐‘ฅ) โˆฉ ๐‘ฆ) = โˆ…))
 
TheoremonfrALTlem4 42590* Lemma for onfrALT 42596. (Contributed by Alan Sare, 22-Jul-2012.) (Proof modification is discouraged.) (New usage is discouraged.)
([๐‘ฆ / ๐‘ฅ](๐‘ฅ โˆˆ ๐‘Ž โˆง (๐‘Ž โˆฉ ๐‘ฅ) = โˆ…) โ†” (๐‘ฆ โˆˆ ๐‘Ž โˆง (๐‘Ž โˆฉ ๐‘ฆ) = โˆ…))
 
TheoremonfrALTlem3 42591* Lemma for onfrALT 42596. (Contributed by Alan Sare, 22-Jul-2012.) (Proof modification is discouraged.) (New usage is discouraged.)
((๐‘Ž โŠ† On โˆง ๐‘Ž โ‰  โˆ…) โ†’ ((๐‘ฅ โˆˆ ๐‘Ž โˆง ยฌ (๐‘Ž โˆฉ ๐‘ฅ) = โˆ…) โ†’ โˆƒ๐‘ฆ โˆˆ (๐‘Ž โˆฉ ๐‘ฅ)((๐‘Ž โˆฉ ๐‘ฅ) โˆฉ ๐‘ฆ) = โˆ…))
 
Theoremggen31 42592* gen31 42668 without virtual deductions. (Contributed by Alan Sare, 22-Jul-2012.) (Proof modification is discouraged.) (New usage is discouraged.)
(๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ ๐œƒ)))    โ‡’   (๐œ‘ โ†’ (๐œ“ โ†’ (๐œ’ โ†’ โˆ€๐‘ฅ๐œƒ)))
 
TheoremonfrALTlem2 42593* Lemma for onfrALT 42596. (Contributed by Alan Sare, 22-Jul-2012.) (Proof modification is discouraged.) (New usage is discouraged.)
((๐‘Ž โŠ† On โˆง ๐‘Ž โ‰  โˆ…) โ†’ ((๐‘ฅ โˆˆ ๐‘Ž โˆง ยฌ (๐‘Ž โˆฉ ๐‘ฅ) = โˆ…) โ†’ โˆƒ๐‘ฆ โˆˆ ๐‘Ž (๐‘Ž โˆฉ ๐‘ฆ) = โˆ…))
 
Theoremcbvexsv 42594* A theorem pertaining to the substitution for an existentially quantified variable when the substituted variable does not occur in the quantified wff. (Contributed by Alan Sare, 22-Jul-2012.) (Proof modification is discouraged.) (New usage is discouraged.)
(โˆƒ๐‘ฅ๐œ‘ โ†” โˆƒ๐‘ฆ[๐‘ฆ / ๐‘ฅ]๐œ‘)
 
TheoremonfrALTlem1 42595* Lemma for onfrALT 42596. (Contributed by Alan Sare, 22-Jul-2012.) (Proof modification is discouraged.) (New usage is discouraged.)
((๐‘Ž โŠ† On โˆง ๐‘Ž โ‰  โˆ…) โ†’ ((๐‘ฅ โˆˆ ๐‘Ž โˆง (๐‘Ž โˆฉ ๐‘ฅ) = โˆ…) โ†’ โˆƒ๐‘ฆ โˆˆ ๐‘Ž (๐‘Ž โˆฉ ๐‘ฆ) = โˆ…))
 
TheoremonfrALT 42596 The membership relation is foundational on the class of ordinal numbers. onfrALT 42596 is an alternate proof of onfr 6353. onfrALTVD 42938 is the Virtual Deduction proof from which onfrALT 42596 is derived. The Virtual Deduction proof mirrors the working proof of onfr 6353 which is the main part of the proof of Theorem 7.12 of the first edition of TakeutiZaring. The proof of the corresponding Proposition 7.12 of [TakeutiZaring] p. 38 (second edition) does not contain the working proof equivalent of onfrALTVD 42938. This theorem does not rely on the Axiom of Regularity. (Contributed by Alan Sare, 22-Jul-2012.) (Proof modification is discouraged.) (New usage is discouraged.)
E Fr On
 
Theorem19.41rg 42597 Closed form of right-to-left implication of 19.41 2229, Theorem 19.41 of [Margaris] p. 90. Derived from 19.41rgVD 42949. (Contributed by Alan Sare, 8-Feb-2014.) (Proof modification is discouraged.) (New usage is discouraged.)
(โˆ€๐‘ฅ(๐œ“ โ†’ โˆ€๐‘ฅ๐œ“) โ†’ ((โˆƒ๐‘ฅ๐œ‘ โˆง ๐œ“) โ†’ โˆƒ๐‘ฅ(๐œ‘ โˆง ๐œ“)))
 
Theoremopelopab4 42598* Ordered pair membership in a class abstraction of ordered pairs. Compare to elopab 5482. (Contributed by Alan Sare, 8-Feb-2014.) (Revised by Mario Carneiro, 6-May-2015.) (Proof modification is discouraged.) (New usage is discouraged.)
(โŸจ๐‘ข, ๐‘ฃโŸฉ โˆˆ {โŸจ๐‘ฅ, ๐‘ฆโŸฉ โˆฃ ๐œ‘} โ†” โˆƒ๐‘ฅโˆƒ๐‘ฆ((๐‘ฅ = ๐‘ข โˆง ๐‘ฆ = ๐‘ฃ) โˆง ๐œ‘))
 
Theorem2pm13.193 42599 pm13.193 42456 for two variables. pm13.193 42456 is Theorem *13.193 in [WhiteheadRussell] p. 179. Derived from 2pm13.193VD 42950. (Contributed by Alan Sare, 8-Feb-2014.) (Proof modification is discouraged.) (New usage is discouraged.)
(((๐‘ฅ = ๐‘ข โˆง ๐‘ฆ = ๐‘ฃ) โˆง [๐‘ข / ๐‘ฅ][๐‘ฃ / ๐‘ฆ]๐œ‘) โ†” ((๐‘ฅ = ๐‘ข โˆง ๐‘ฆ = ๐‘ฃ) โˆง ๐œ‘))
 
Theoremhbntal 42600 A closed form of hbn 2293. hbnt 2292 is another closed form of hbn 2293. (Contributed by Alan Sare, 8-Feb-2014.) (Proof modification is discouraged.) (New usage is discouraged.)
(โˆ€๐‘ฅ(๐œ‘ โ†’ โˆ€๐‘ฅ๐œ‘) โ†’ โˆ€๐‘ฅ(ยฌ ๐œ‘ โ†’ โˆ€๐‘ฅ ยฌ ๐œ‘))
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78 7701-7800 79 7801-7900 80 7901-8000 81 8001-8100 82 8101-8200 83 8201-8300 84 8301-8400 85 8401-8500 86 8501-8600 87 8601-8700 88 8701-8800 89 8801-8900 90 8901-9000 91 9001-9100 92 9101-9200 93 9201-9300 94 9301-9400 95 9401-9500 96 9501-9600 97 9601-9700 98 9701-9800 99 9801-9900 100 9901-10000 101 10001-10100 102 10101-10200 103 10201-10300 104 10301-10400 105 10401-10500 106 10501-10600 107 10601-10700 108 10701-10800 109 10801-10900 110 10901-11000 111 11001-11100 112 11101-11200 113 11201-11300 114 11301-11400 115 11401-11500 116 11501-11600 117 11601-11700 118 11701-11800 119 11801-11900 120 11901-12000 121 12001-12100 122 12101-12200 123 12201-12300 124 12301-12400 125 12401-12500 126 12501-12600 127 12601-12700 128 12701-12800 129 12801-12900 130 12901-13000 131 13001-13100 132 13101-13200 133 13201-13300 134 13301-13400 135 13401-13500 136 13501-13600 137 13601-13700 138 13701-13800 139 13801-13900 140 13901-14000 141 14001-14100 142 14101-14200 143 14201-14300 144 14301-14400 145 14401-14500 146 14501-14600 147 14601-14700 148 14701-14800 149 14801-14900 150 14901-15000 151 15001-15100 152 15101-15200 153 15201-15300 154 15301-15400 155 15401-15500 156 15501-15600 157 15601-15700 158 15701-15800 159 15801-15900 160 15901-16000 161 16001-16100 162 16101-16200 163 16201-16300 164 16301-16400 165 16401-16500 166 16501-16600 167 16601-16700 168 16701-16800 169 16801-16900 170 16901-17000 171 17001-17100 172 17101-17200 173 17201-17300 174 17301-17400 175 17401-17500 176 17501-17600 177 17601-17700 178 17701-17800 179 17801-17900 180 17901-18000 181 18001-18100 182 18101-18200 183 18201-18300 184 18301-18400 185 18401-18500 186 18501-18600 187 18601-18700 188 18701-18800 189 18801-18900 190 18901-19000 191 19001-19100 192 19101-19200 193 19201-19300 194 19301-19400 195 19401-19500 196 19501-19600 197 19601-19700 198 19701-19800 199 19801-19900 200 19901-20000 201 20001-20100 202 20101-20200 203 20201-20300 204 20301-20400 205 20401-20500 206 20501-20600 207 20601-20700 208 20701-20800 209 20801-20900 210 20901-21000 211 21001-21100 212 21101-21200 213 21201-21300 214 21301-21400 215 21401-21500 216 21501-21600 217 21601-21700 218 21701-21800 219 21801-21900 220 21901-22000 221 22001-22100 222 22101-22200 223 22201-22300 224 22301-22400 225 22401-22500 226 22501-22600 227 22601-22700 228 22701-22800 229 22801-22900 230 22901-23000 231 23001-23100 232 23101-23200 233 23201-23300 234 23301-23400 235 23401-23500 236 23501-23600 237 23601-23700 238 23701-23800 239 23801-23900 240 23901-24000 241 24001-24100 242 24101-24200 243 24201-24300 244 24301-24400 245 24401-24500 246 24501-24600 247 24601-24700 248 24701-24800 249 24801-24900 250 24901-25000 251 25001-25100 252 25101-25200 253 25201-25300 254 25301-25400 255 25401-25500 256 25501-25600 257 25601-25700 258 25701-25800 259 25801-25900 260 25901-26000 261 26001-26100 262 26101-26200 263 26201-26300 264 26301-26400 265 26401-26500 266 26501-26600 267 26601-26700 268 26701-26800 269 26801-26900 270 26901-27000 271 27001-27100 272 27101-27200 273 27201-27300 274 27301-27400 275 27401-27500 276 27501-27600 277 27601-27700 278 27701-27800 279 27801-27900 280 27901-28000 281 28001-28100 282 28101-28200 283 28201-28300 284 28301-28400 285 28401-28500 286 28501-28600 287 28601-28700 288 28701-28800 289 28801-28900 290 28901-29000 291 29001-29100 292 29101-29200 293 29201-29300 294 29301-29400 295 29401-29500 296 29501-29600 297 29601-29700 298 29701-29800 299 29801-29900 300 29901-30000 301 30001-30100 302 30101-30200 303 30201-30300 304 30301-30400 305 30401-30500 306 30501-30600 307 30601-30700 308 30701-30800 309 30801-30900 310 30901-31000 311 31001-31100 312 31101-31200 313 31201-31300 314 31301-31400 315 31401-31500 316 31501-31600 317 31601-31700 318 31701-31800 319 31801-31900 320 31901-32000 321 32001-32100 322 32101-32200 323 32201-32300 324 32301-32400 325 32401-32500 326 32501-32600 327 32601-32700 328 32701-32800 329 32801-32900 330 32901-33000 331 33001-33100 332 33101-33200 333 33201-33300 334 33301-33400 335 33401-33500 336 33501-33600 337 33601-33700 338 33701-33800 339 33801-33900 340 33901-34000 341 34001-34100 342 34101-34200 343 34201-34300 344 34301-34400 345 34401-34500 346 34501-34600 347 34601-34700 348 34701-34800 349 34801-34900 350 34901-35000 351 35001-35100 352 35101-35200 353 35201-35300 354 35301-35400 355 35401-35500 356 35501-35600 357 35601-35700 358 35701-35800 359 35801-35900 360 35901-36000 361 36001-36100 362 36101-36200 363 36201-36300 364 36301-36400 365 36401-36500 366 36501-36600 367 36601-36700 368 36701-36800 369 36801-36900 370 36901-37000 371 37001-37100 372 37101-37200 373 37201-37300 374 37301-37400 375 37401-37500 376 37501-37600 377 37601-37700 378 37701-37800 379 37801-37900 380 37901-38000 381 38001-38100 382 38101-38200 383 38201-38300 384 38301-38400 385 38401-38500 386 38501-38600 387 38601-38700 388 38701-38800 389 38801-38900 390 38901-39000 391 39001-39100 392 39101-39200 393 39201-39300 394 39301-39400 395 39401-39500 396 39501-39600 397 39601-39700 398 39701-39800 399 39801-39900 400 39901-40000 401 40001-40100 402 40101-40200 403 40201-40300 404 40301-40400 405 40401-40500 406 40501-40600 407 40601-40700 408 40701-40800 409 40801-40900 410 40901-41000 411 41001-41100 412 41101-41200 413 41201-41300 414 41301-41400 415 41401-41500 416 41501-41600 417 41601-41700 418 41701-41800 419 41801-41900 420 41901-42000 421 42001-42100 422 42101-42200 423 42201-42300 424 42301-42400 425 42401-42500 426 42501-42600 427 42601-42700 428 42701-42800 429 42801-42900 430 42901-43000 431 43001-43100 432 43101-43200 433 43201-43300 434 43301-43400 435 43401-43500 436 43501-43600 437 43601-43700 438 43701-43800 439 43801-43900 440 43901-44000 441 44001-44100 442 44101-44200 443 44201-44300 444 44301-44400 445 44401-44500 446 44501-44600 447 44601-44700 448 44701-44800 449 44801-44900 450 44901-45000 451 45001-45100 452 45101-45200 453 45201-45300 454 45301-45400 455 45401-45500 456 45501-45600 457 45601-45700 458 45701-45800 459 45801-45900 460 45901-46000 461 46001-46100 462 46101-46200 463 46201-46300 464 46301-46400 465 46401-46500 466 46501-46600 467 46601-46700 468 46701-46800 469 46801-46900 470 46901-46998
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