P. 32 of Theorem List - Metamath Proof Explorer

Theorem List for Metamath Proof Explorer - 3101-3200   *Has distinct variable group(s)

Type	Label	Description
Statement
Theorem	cbvral2v 3101*	Change bound variables of double restricted universal quantification, using implicit substitution. (Contributed by NM, 10-Aug-2004.)
|- ( x = z -> ( ph <-> ch ) )   &    |- ( y = w -> ( ch <-> ps ) )   =>    |- ( A. x e. A A. y e. B ph <-> A. z e. A A. w e. B ps )
Theorem	cbvrex2v 3102*	Change bound variables of double restricted universal quantification, using implicit substitution. (Contributed by FL, 2-Jul-2012.)
|- ( x = z -> ( ph <-> ch ) )   &    |- ( y = w -> ( ch <-> ps ) )   =>    |- ( E. x e. A E. y e. B ph <-> E. z e. A E. w e. B ps )
Theorem	cbvral3v 3103*	Change bound variables of triple restricted universal quantification, using implicit substitution. (Contributed by NM, 10-May-2005.)
|- ( x = w -> ( ph <-> ch ) )   &    |- ( y = v -> ( ch <-> th ) )   &    |- ( z = u -> ( th <-> ps ) )   =>    |- ( A. x e. A A. y e. B A. z e. C ph <-> A. w e. A A. v e. B A. u e. C ps )
Theorem	cbvralsv 3104*	Change bound variable by using a substitution. (Contributed by NM, 20-Nov-2005.) (Revised by Andrew Salmon, 11-Jul-2011.)
|- ( A. x e. A ph <-> A. y e. A [ y / x ] ph )
Theorem	cbvrexsv 3105*	Change bound variable by using a substitution. (Contributed by NM, 2-Mar-2008.) (Revised by Andrew Salmon, 11-Jul-2011.)
|- ( E. x e. A ph <-> E. y e. A [ y / x ] ph )
Theorem	sbralie 3106*	Implicit to explicit substitution that swaps variables in a quantified expression. (Contributed by NM, 5-Sep-2004.)
|- ( x = y -> ( ph <-> ps ) )   =>    |- ( [ x / y ] A. x e. y ph <-> A. y e. x ps )
Theorem	rabbiia 3107	Equivalent wff's yield equal restricted class abstractions (inference rule). (Contributed by NM, 22-May-1999.)
|- ( x e. A -> ( ph <-> ps ) )   =>    |- { x e. A | ph } = { x e. A | ps }
Theorem	rabbidva2 3108*	Equivalent wff's yield equal restricted class abstractions. (Contributed by Thierry Arnoux, 4-Feb-2017.)
|- ( ph -> ( ( x e. A /\ ps ) <-> ( x e. B /\ ch ) ) )   =>    |- ( ph -> { x e. A | ps } = { x e. B | ch } )
Theorem	rabbidva 3109*	Equivalent wff's yield equal restricted class abstractions (deduction rule). (Contributed by NM, 28-Nov-2003.)
|- ( ( ph /\ x e. A ) -> ( ps <-> ch ) )   =>    |- ( ph -> { x e. A | ps } = { x e. A | ch } )
Theorem	rabbidv 3110*	Equivalent wff's yield equal restricted class abstractions (deduction rule). (Contributed by NM, 10-Feb-1995.)
|- ( ph -> ( ps <-> ch ) )   =>    |- ( ph -> { x e. A | ps } = { x e. A | ch } )
Theorem	rabeqf 3111	Equality theorem for restricted class abstractions, with bound-variable hypotheses instead of distinct variable restrictions. (Contributed by NM, 7-Mar-2004.)
|- F/_ x A   &    |- F/_ x B   =>    |- ( A = B -> { x e. A | ph } = { x e. B | ph } )
Theorem	rabeq 3112*	Equality theorem for restricted class abstractions. (Contributed by NM, 15-Oct-2003.)
|- ( A = B -> { x e. A | ph } = { x e. B | ph } )
Theorem	rabeqbidv 3113*	Equality of restricted class abstractions. (Contributed by Jeff Madsen, 1-Dec-2009.)
|- ( ph -> A = B )   &    |- ( ph -> ( ps <-> ch ) )   =>    |- ( ph -> { x e. A | ps } = { x e. B | ch } )
Theorem	rabeqbidva 3114*	Equality of restricted class abstractions. (Contributed by Mario Carneiro, 26-Jan-2017.)
|- ( ph -> A = B )   &    |- ( ( ph /\ x e. A ) -> ( ps <-> ch ) )   =>    |- ( ph -> { x e. A | ps } = { x e. B | ch } )
Theorem	rabeq2i 3115	Inference rule from equality of a class variable and a restricted class abstraction. (Contributed by NM, 16-Feb-2004.)
|- A = { x e. B | ph }   =>    |- ( x e. A <-> ( x e. B /\ ph ) )
Theorem	cbvrab 3116	Rule to change the bound variable in a restricted class abstraction, using implicit substitution. This version has bound-variable hypotheses in place of distinct variable conditions. (Contributed by Andrew Salmon, 11-Jul-2011.) (Revised by Mario Carneiro, 9-Oct-2016.)
|- F/_ x A   &    |- F/_ y A   &    |- F/ y ph   &    |- F/ x ps   &    |- ( x = y -> ( ph <-> ps ) )   =>    |- { x e. A | ph } = { y e. A | ps }
Theorem	cbvrabv 3117*	Rule to change the bound variable in a restricted class abstraction, using implicit substitution. (Contributed by NM, 26-May-1999.)
|- ( x = y -> ( ph <-> ps ) )   =>    |- { x e. A | ph } = { y e. A | ps }
2.1.6  The universal class
Syntax	cvv 3118	Extend class notation to include the universal class symbol.
class _V
Theorem	vjust 3119	Soundness justification theorem for df-v 3120. (Contributed by Rodolfo Medina, 27-Apr-2010.)
|- { x | x = x } = { y | y = y }
Definition	df-v 3120	Define the universal class. Definition 5.20 of [TakeutiZaring] p. 21. Also Definition 2.9 of [Quine] p. 19. The class _V can be described as the "class of all sets"; vprc 4591 proves that _V is not itself a set in ZFC. We will frequently use the expression A e. _V as a short way to say " A is a set", and isset 3122 proves that this expression has the same meaning as E. x x = A. The class _V is called the "von Neumann universe", however, the letter "V" is not a tribute to the name of von Neumann. The letter "V" was used earlier by Peano in 1889 for the universe of sets, where the letter V is derived from the word "Verum". Peano's notation V was adopted by Whitehead and Russell in Principia Mathematica for the class of all sets in 1910. For a general discussion of the theory of classes, see http://us.metamath.org/mpeuni/mmset.html#class. (Contributed by NM, 26-May-1993.)
|- _V = { x | x = x }
Theorem	vex 3121	All setvar variables are sets (see isset 3122). Theorem 6.8 of [Quine] p. 43. (Contributed by NM, 26-May-1993.)
|- x e. _V
Theorem	isset 3122*	Two ways to say " A is a set": A class A is a member of the universal class _V (see df-v 3120) if and only if the class A exists (i.e. there exists some set x equal to class A). Theorem 6.9 of [Quine] p. 43. Notational convention: We will use the notational device " A e. _V " to mean " A is a set" very frequently, for example in uniex 6591. Note the when A is not a set, it is called a proper class. In some theorems, such as uniexg 6592, in order to shorten certain proofs we use the more general antecedent A e. V instead of A e. _V to mean " A is a set." Note that a constant is implicitly considered distinct from all variables. This is why _V is not included in the distinct variable list, even though df-clel 2462 requires that the expression substituted for B not contain x. (Also, the Metamath spec does not allow constants in the distinct variable list.) (Contributed by NM, 26-May-1993.)
|- ( A e. _V <-> E. x x = A )
Theorem	issetf 3123	A version of isset 3122 that does not require x and A to be distinct. (Contributed by Andrew Salmon, 6-Jun-2011.) (Revised by Mario Carneiro, 10-Oct-2016.)
|- F/_ x A   =>    |- ( A e. _V <-> E. x x = A )
Theorem	isseti 3124*	A way to say " A is a set" (inference rule). (Contributed by NM, 24-Jun-1993.)
|- A e. _V   =>    |- E. x x = A
Theorem	issetri 3125*	A way to say " A is a set" (inference rule). (Contributed by NM, 21-Jun-1993.)
|- E. x x = A   =>    |- A e. _V
Theorem	eqvisset 3126	A class equal to a variable is a set. Note the absence of dv condition, contrary to isset 3122 and issetri 3125. (Contributed by BJ, 27-Apr-2019.)
|- ( x = A -> A e. _V )
Theorem	elex 3127	If a class is a member of another class, it is a set. Theorem 6.12 of [Quine] p. 44. (Contributed by NM, 26-May-1993.) (Proof shortened by Andrew Salmon, 8-Jun-2011.)
|- ( A e. B -> A e. _V )
Theorem	elexi 3128	If a class is a member of another class, it is a set. (Contributed by NM, 11-Jun-1994.)
|- A e. B   =>    |- A e. _V
Theorem	elisset 3129*	An element of a class exists. (Contributed by NM, 1-May-1995.)
|- ( A e. V -> E. x x = A )
Theorem	elex2 3130*	If a class contains another class, then it contains some set. (Contributed by Alan Sare, 25-Sep-2011.)
|- ( A e. B -> E. x x e. B )
Theorem	elex22 3131*	If two classes each contain another class, then both contain some set. (Contributed by Alan Sare, 24-Oct-2011.)
|- ( ( A e. B /\ A e. C ) -> E. x ( x e. B /\ x e. C ) )
Theorem	ralv 3132	A universal quantifier restricted to the universe is unrestricted. (Contributed by NM, 26-Mar-2004.)
|- ( A. x e. _V ph <-> A. x ph )
Theorem	rexv 3133	An existential quantifier restricted to the universe is unrestricted. (Contributed by NM, 26-Mar-2004.)
|- ( E. x e. _V ph <-> E. x ph )
Theorem	reuv 3134	A uniqueness quantifier restricted to the universe is unrestricted. (Contributed by NM, 1-Nov-2010.)
|- ( E! x e. _V ph <-> E! x ph )
Theorem	rmov 3135	A uniqueness quantifier restricted to the universe is unrestricted. (Contributed by Alexander van der Vekens, 17-Jun-2017.)
|- ( E* x e. _V ph <-> E* x ph )
Theorem	rabab 3136	A class abstraction restricted to the universe is unrestricted. (Contributed by NM, 27-Dec-2004.) (Proof shortened by Andrew Salmon, 8-Jun-2011.)
|- { x e. _V | ph } = { x | ph }
Theorem	ralcom4 3137*	Commutation of restricted and unrestricted universal quantifiers. (Contributed by NM, 26-Mar-2004.) (Proof shortened by Andrew Salmon, 8-Jun-2011.)
|- ( A. x e. A A. y ph <-> A. y A. x e. A ph )
Theorem	rexcom4 3138*	Commutation of restricted and unrestricted existential quantifiers. (Contributed by NM, 12-Apr-2004.) (Proof shortened by Andrew Salmon, 8-Jun-2011.)
|- ( E. x e. A E. y ph <-> E. y E. x e. A ph )
Theorem	rexcom4a 3139*	Specialized existential commutation lemma. (Contributed by Jeff Madsen, 1-Jun-2011.)
|- ( E. x E. y e. A ( ph /\ ps ) <-> E. y e. A ( ph /\ E. x ps ) )
Theorem	rexcom4b 3140*	Specialized existential commutation lemma. (Contributed by Jeff Madsen, 1-Jun-2011.)
|- B e. _V   =>    |- ( E. x E. y e. A ( ph /\ x = B ) <-> E. y e. A ph )
Theorem	ceqsalt 3141*	Closed theorem version of ceqsalg 3143. (Contributed by NM, 28-Feb-2013.) (Revised by Mario Carneiro, 10-Oct-2016.)
|- ( ( F/ x ps /\ A. x ( x = A -> ( ph <-> ps ) ) /\ A e. V ) -> ( A. x ( x = A -> ph ) <-> ps ) )
Theorem	ceqsralt 3142*	Restricted quantifier version of ceqsalt 3141. (Contributed by NM, 28-Feb-2013.) (Revised by Mario Carneiro, 10-Oct-2016.)
|- ( ( F/ x ps /\ A. x ( x = A -> ( ph <-> ps ) ) /\ A e. B ) -> ( A. x e. B ( x = A -> ph ) <-> ps ) )
Theorem	ceqsalg 3143*	A representation of explicit substitution of a class for a variable, inferred from an implicit substitution hypothesis. For an alternate proof, see ceqsalgALT 3144. (Contributed by NM, 29-Oct-2003.) (Proof shortened by BJ, 29-Sep-2019.)
|- F/ x ps   &    |- ( x = A -> ( ph <-> ps ) )   =>    |- ( A e. V -> ( A. x ( x = A -> ph ) <-> ps ) )
Theorem	ceqsalgALT 3144*	Alternate proof of ceqsalg 3143, not using ceqsalt 3141. (Contributed by NM, 29-Oct-2003.) (Proof shortened by Andrew Salmon, 8-Jun-2011.) (Revised by BJ, 29-Sep-2019.) (Proof modification is discouraged.) (New usage is discouraged.)
|- F/ x ps   &    |- ( x = A -> ( ph <-> ps ) )   =>    |- ( A e. V -> ( A. x ( x = A -> ph ) <-> ps ) )
Theorem	ceqsal 3145*	A representation of explicit substitution of a class for a variable, inferred from an implicit substitution hypothesis. (Contributed by NM, 18-Aug-1993.)
|- F/ x ps   &    |- A e. _V   &    |- ( x = A -> ( ph <-> ps ) )   =>    |- ( A. x ( x = A -> ph ) <-> ps )
Theorem	ceqsalv 3146*	A representation of explicit substitution of a class for a variable, inferred from an implicit substitution hypothesis. (Contributed by NM, 18-Aug-1993.)
|- A e. _V   &    |- ( x = A -> ( ph <-> ps ) )   =>    |- ( A. x ( x = A -> ph ) <-> ps )
Theorem	ceqsralv 3147*	Restricted quantifier version of ceqsalv 3146. (Contributed by NM, 21-Jun-2013.)
|- ( x = A -> ( ph <-> ps ) )   =>    |- ( A e. B -> ( A. x e. B ( x = A -> ph ) <-> ps ) )
Theorem	gencl 3148*	Implicit substitution for class with embedded variable. (Contributed by NM, 17-May-1996.)
|- ( th <-> E. x ( ch /\ A = B ) )   &    |- ( A = B -> ( ph <-> ps ) )   &    |- ( ch -> ph )   =>    |- ( th -> ps )
Theorem	2gencl 3149*	Implicit substitution for class with embedded variable. (Contributed by NM, 17-May-1996.)
|- ( C e. S <-> E. x e. R A = C )   &    |- ( D e. S <-> E. y e. R B = D )   &    |- ( A = C -> ( ph <-> ps ) )   &    |- ( B = D -> ( ps <-> ch ) )   &    |- ( ( x e. R /\ y e. R ) -> ph )   =>    |- ( ( C e. S /\ D e. S ) -> ch )
Theorem	3gencl 3150*	Implicit substitution for class with embedded variable. (Contributed by NM, 17-May-1996.)
|- ( D e. S <-> E. x e. R A = D )   &    |- ( F e. S <-> E. y e. R B = F )   &    |- ( G e. S <-> E. z e. R C = G )   &    |- ( A = D -> ( ph <-> ps ) )   &    |- ( B = F -> ( ps <-> ch ) )   &    |- ( C = G -> ( ch <-> th ) )   &    |- ( ( x e. R /\ y e. R /\ z e. R ) -> ph )   =>    |- ( ( D e. S /\ F e. S /\ G e. S ) -> th )
Theorem	cgsexg 3151*	Implicit substitution inference for general classes. (Contributed by NM, 26-Aug-2007.)
|- ( x = A -> ch )   &    |- ( ch -> ( ph <-> ps ) )   =>    |- ( A e. V -> ( E. x ( ch /\ ph ) <-> ps ) )
Theorem	cgsex2g 3152*	Implicit substitution inference for general classes. (Contributed by NM, 26-Jul-1995.)
|- ( ( x = A /\ y = B ) -> ch )   &    |- ( ch -> ( ph <-> ps ) )   =>    |- ( ( A e. V /\ B e. W ) -> ( E. x E. y ( ch /\ ph ) <-> ps ) )
Theorem	cgsex4g 3153*	An implicit substitution inference for 4 general classes. (Contributed by NM, 5-Aug-1995.)
|- ( ( ( x = A /\ y = B ) /\ ( z = C /\ w = D ) ) -> ch )   &    |- ( ch -> ( ph <-> ps ) )   =>    |- ( ( ( A e. R /\ B e. S ) /\ ( C e. R /\ D e. S ) ) -> ( E. x E. y E. z E. w ( ch /\ ph ) <-> ps ) )
Theorem	ceqsex 3154*	Elimination of an existential quantifier, using implicit substitution. (Contributed by NM, 2-Mar-1995.) (Revised by Mario Carneiro, 10-Oct-2016.)
|- F/ x ps   &    |- A e. _V   &    |- ( x = A -> ( ph <-> ps ) )   =>    |- ( E. x ( x = A /\ ph ) <-> ps )
Theorem	ceqsexv 3155*	Elimination of an existential quantifier, using implicit substitution. (Contributed by NM, 2-Mar-1995.)
|- A e. _V   &    |- ( x = A -> ( ph <-> ps ) )   =>    |- ( E. x ( x = A /\ ph ) <-> ps )
Theorem	ceqsex2 3156*	Elimination of two existential quantifiers, using implicit substitution. (Contributed by Scott Fenton, 7-Jun-2006.)
|- F/ x ps   &    |- F/ y ch   &    |- A e. _V   &    |- B e. _V   &    |- ( x = A -> ( ph <-> ps ) )   &    |- ( y = B -> ( ps <-> ch ) )   =>    |- ( E. x E. y ( x = A /\ y = B /\ ph ) <-> ch )
Theorem	ceqsex2v 3157*	Elimination of two existential quantifiers, using implicit substitution. (Contributed by Scott Fenton, 7-Jun-2006.)
|- A e. _V   &    |- B e. _V   &    |- ( x = A -> ( ph <-> ps ) )   &    |- ( y = B -> ( ps <-> ch ) )   =>    |- ( E. x E. y ( x = A /\ y = B /\ ph ) <-> ch )
Theorem	ceqsex3v 3158*	Elimination of three existential quantifiers, using implicit substitution. (Contributed by NM, 16-Aug-2011.)
|- A e. _V   &    |- B e. _V   &    |- C e. _V   &    |- ( x = A -> ( ph <-> ps ) )   &    |- ( y = B -> ( ps <-> ch ) )   &    |- ( z = C -> ( ch <-> th ) )   =>    |- ( E. x E. y E. z ( ( x = A /\ y = B /\ z = C ) /\ ph ) <-> th )
Theorem	ceqsex4v 3159*	Elimination of four existential quantifiers, using implicit substitution. (Contributed by NM, 23-Sep-2011.)
|- A e. _V   &    |- B e. _V   &    |- C e. _V   &    |- D e. _V   &    |- ( x = A -> ( ph <-> ps ) )   &    |- ( y = B -> ( ps <-> ch ) )   &    |- ( z = C -> ( ch <-> th ) )   &    |- ( w = D -> ( th <-> ta ) )   =>    |- ( E. x E. y E. z E. w ( ( x = A /\ y = B ) /\ ( z = C /\ w = D ) /\ ph ) <-> ta )
Theorem	ceqsex6v 3160*	Elimination of six existential quantifiers, using implicit substitution. (Contributed by NM, 21-Sep-2011.)
|- A e. _V   &    |- B e. _V   &    |- C e. _V   &    |- D e. _V   &    |- E e. _V   &    |- F e. _V   &    |- ( x = A -> ( ph <-> ps ) )   &    |- ( y = B -> ( ps <-> ch ) )   &    |- ( z = C -> ( ch <-> th ) )   &    |- ( w = D -> ( th <-> ta ) )   &    |- ( v = E -> ( ta <-> et ) )   &    |- ( u = F -> ( et <-> ze ) )   =>    |- ( E. x E. y E. z E. w E. v E. u ( ( x = A /\ y = B /\ z = C ) /\ ( w = D /\ v = E /\ u = F ) /\ ph ) <-> ze )
Theorem	ceqsex8v 3161*	Elimination of eight existential quantifiers, using implicit substitution. (Contributed by NM, 23-Sep-2011.)
|- A e. _V   &    |- B e. _V   &    |- C e. _V   &    |- D e. _V   &    |- E e. _V   &    |- F e. _V   &    |- G e. _V   &    |- H e. _V   &    |- ( x = A -> ( ph <-> ps ) )   &    |- ( y = B -> ( ps <-> ch ) )   &    |- ( z = C -> ( ch <-> th ) )   &    |- ( w = D -> ( th <-> ta ) )   &    |- ( v = E -> ( ta <-> et ) )   &    |- ( u = F -> ( et <-> ze ) )   &    |- ( t = G -> ( ze <-> si ) )   &    |- ( s = H -> ( si <-> rh ) )   =>    |- ( E. x E. y E. z E. w E. v E. u E. t E. s ( ( ( x = A /\ y = B ) /\ ( z = C /\ w = D ) ) /\ ( ( v = E /\ u = F ) /\ ( t = G /\ s = H ) ) /\ ph ) <-> rh )
Theorem	gencbvex 3162*	Change of bound variable using implicit substitution. (Contributed by NM, 17-May-1996.) (Proof shortened by Andrew Salmon, 8-Jun-2011.)
|- A e. _V   &    |- ( A = y -> ( ph <-> ps ) )   &    |- ( A = y -> ( ch <-> th ) )   &    |- ( th <-> E. x ( ch /\ A = y ) )   =>    |- ( E. x ( ch /\ ph ) <-> E. y ( th /\ ps ) )
Theorem	gencbvex2 3163*	Restatement of gencbvex 3162 with weaker hypotheses. (Contributed by Jeff Hankins, 6-Dec-2006.)
|- A e. _V   &    |- ( A = y -> ( ph <-> ps ) )   &    |- ( A = y -> ( ch <-> th ) )   &    |- ( th -> E. x ( ch /\ A = y ) )   =>    |- ( E. x ( ch /\ ph ) <-> E. y ( th /\ ps ) )
Theorem	gencbval 3164*	Change of bound variable using implicit substitution. (Contributed by NM, 17-May-1996.)
|- A e. _V   &    |- ( A = y -> ( ph <-> ps ) )   &    |- ( A = y -> ( ch <-> th ) )   &    |- ( th <-> E. x ( ch /\ A = y ) )   =>    |- ( A. x ( ch -> ph ) <-> A. y ( th -> ps ) )
Theorem	sbhypf 3165*	Introduce an explicit substitution into an implicit substitution hypothesis. See also csbhypf 3459. (Contributed by Raph Levien, 10-Apr-2004.)
|- F/ x ps   &    |- ( x = A -> ( ph <-> ps ) )   =>    |- ( y = A -> ( [ y / x ] ph <-> ps ) )
Theorem	vtoclgft 3166	Closed theorem form of vtoclgf 3174. (Contributed by NM, 17-Feb-2013.) (Revised by Mario Carneiro, 12-Oct-2016.)
|- ( ( ( F/_ x A /\ F/ x ps ) /\ ( A. x ( x = A -> ( ph <-> ps ) ) /\ A. x ph ) /\ A e. V ) -> ps )
Theorem	vtocldf 3167	Implicit substitution of a class for a setvar variable. (Contributed by Mario Carneiro, 15-Oct-2016.)
|- ( ph -> A e. V )   &    |- ( ( ph /\ x = A ) -> ( ps <-> ch ) )   &    |- ( ph -> ps )   &    |- F/ x ph   &    |- ( ph -> F/_ x A )   &    |- ( ph -> F/ x ch )   =>    |- ( ph -> ch )
Theorem	vtocld 3168*	Implicit substitution of a class for a setvar variable. (Contributed by Mario Carneiro, 15-Oct-2016.)
|- ( ph -> A e. V )   &    |- ( ( ph /\ x = A ) -> ( ps <-> ch ) )   &    |- ( ph -> ps )   =>    |- ( ph -> ch )
Theorem	vtoclf 3169*	Implicit substitution of a class for a setvar variable. This is a generalization of chvar 1982. (Contributed by NM, 30-Aug-1993.)
|- F/ x ps   &    |- A e. _V   &    |- ( x = A -> ( ph <-> ps ) )   &    |- ph   =>    |- ps
Theorem	vtocl 3170*	Implicit substitution of a class for a setvar variable. (Contributed by NM, 30-Aug-1993.)
|- A e. _V   &    |- ( x = A -> ( ph <-> ps ) )   &    |- ph   =>    |- ps
Theorem	vtocl2 3171*	Implicit substitution of classes for setvar variables. (Contributed by NM, 26-Jul-1995.) (Proof shortened by Andrew Salmon, 8-Jun-2011.)
|- A e. _V   &    |- B e. _V   &    |- ( ( x = A /\ y = B ) -> ( ph <-> ps ) )   &    |- ph   =>    |- ps
Theorem	vtocl3 3172*	Implicit substitution of classes for setvar variables. (Contributed by NM, 3-Jun-1995.) (Proof shortened by Andrew Salmon, 8-Jun-2011.)
|- A e. _V   &    |- B e. _V   &    |- C e. _V   &    |- ( ( x = A /\ y = B /\ z = C ) -> ( ph <-> ps ) )   &    |- ph   =>    |- ps
Theorem	vtoclb 3173*	Implicit substitution of a class for a setvar variable. (Contributed by NM, 23-Dec-1993.)
|- A e. _V   &    |- ( x = A -> ( ph <-> ch ) )   &    |- ( x = A -> ( ps <-> th ) )   &    |- ( ph <-> ps )   =>    |- ( ch <-> th )
Theorem	vtoclgf 3174	Implicit substitution of a class for a setvar variable, with bound-variable hypotheses in place of disjoint variable restrictions. (Contributed by NM, 21-Sep-2003.) (Proof shortened by Mario Carneiro, 10-Oct-2016.)
|- F/_ x A   &    |- F/ x ps   &    |- ( x = A -> ( ph <-> ps ) )   &    |- ph   =>    |- ( A e. V -> ps )
Theorem	vtoclg1f 3175*	Version of vtoclgf 3174 with one non-freeness hypothesis replaced with a dv condition, thus avoiding dependency on ax-11 1791 and ax-13 1968. (Contributed by BJ, 1-May-2019.)
|- F/ x ps   &    |- ( x = A -> ( ph <-> ps ) )   &    |- ph   =>    |- ( A e. V -> ps )
Theorem	vtoclg 3176*	Implicit substitution of a class expression for a setvar variable. (Contributed by NM, 17-Apr-1995.)
|- ( x = A -> ( ph <-> ps ) )   &    |- ph   =>    |- ( A e. V -> ps )
Theorem	vtoclbg 3177*	Implicit substitution of a class for a setvar variable. (Contributed by NM, 29-Apr-1994.)
|- ( x = A -> ( ph <-> ch ) )   &    |- ( x = A -> ( ps <-> th ) )   &    |- ( ph <-> ps )   =>    |- ( A e. V -> ( ch <-> th ) )
Theorem	vtocl2gf 3178	Implicit substitution of a class for a setvar variable. (Contributed by NM, 25-Apr-1995.)
|- F/_ x A   &    |- F/_ y A   &    |- F/_ y B   &    |- F/ x ps   &    |- F/ y ch   &    |- ( x = A -> ( ph <-> ps ) )   &    |- ( y = B -> ( ps <-> ch ) )   &    |- ph   =>    |- ( ( A e. V /\ B e. W ) -> ch )
Theorem	vtocl3gf 3179	Implicit substitution of a class for a setvar variable. (Contributed by NM, 10-Aug-2013.) (Revised by Mario Carneiro, 10-Oct-2016.)
|- F/_ x A   &    |- F/_ y A   &    |- F/_ z A   &    |- F/_ y B   &    |- F/_ z B   &    |- F/_ z C   &    |- F/ x ps   &    |- F/ y ch   &    |- F/ z th   &    |- ( x = A -> ( ph <-> ps ) )   &    |- ( y = B -> ( ps <-> ch ) )   &    |- ( z = C -> ( ch <-> th ) )   &    |- ph   =>    |- ( ( A e. V /\ B e. W /\ C e. X ) -> th )
Theorem	vtocl2g 3180*	Implicit substitution of 2 classes for 2 setvar variables. (Contributed by NM, 25-Apr-1995.)
|- ( x = A -> ( ph <-> ps ) )   &    |- ( y = B -> ( ps <-> ch ) )   &    |- ph   =>    |- ( ( A e. V /\ B e. W ) -> ch )
Theorem	vtoclgaf 3181*	Implicit substitution of a class for a setvar variable. (Contributed by NM, 17-Feb-2006.) (Revised by Mario Carneiro, 10-Oct-2016.)
|- F/_ x A   &    |- F/ x ps   &    |- ( x = A -> ( ph <-> ps ) )   &    |- ( x e. B -> ph )   =>    |- ( A e. B -> ps )
Theorem	vtoclga 3182*	Implicit substitution of a class for a setvar variable. (Contributed by NM, 20-Aug-1995.)
|- ( x = A -> ( ph <-> ps ) )   &    |- ( x e. B -> ph )   =>    |- ( A e. B -> ps )
Theorem	vtocl2gaf 3183*	Implicit substitution of 2 classes for 2 setvar variables. (Contributed by NM, 10-Aug-2013.)
|- F/_ x A   &    |- F/_ y A   &    |- F/_ y B   &    |- F/ x ps   &    |- F/ y ch   &    |- ( x = A -> ( ph <-> ps ) )   &    |- ( y = B -> ( ps <-> ch ) )   &    |- ( ( x e. C /\ y e. D ) -> ph )   =>    |- ( ( A e. C /\ B e. D ) -> ch )
Theorem	vtocl2ga 3184*	Implicit substitution of 2 classes for 2 setvar variables. (Contributed by NM, 20-Aug-1995.)
|- ( x = A -> ( ph <-> ps ) )   &    |- ( y = B -> ( ps <-> ch ) )   &    |- ( ( x e. C /\ y e. D ) -> ph )   =>    |- ( ( A e. C /\ B e. D ) -> ch )
Theorem	vtocl3gaf 3185*	Implicit substitution of 3 classes for 3 setvar variables. (Contributed by NM, 10-Aug-2013.) (Revised by Mario Carneiro, 11-Oct-2016.)
|- F/_ x A   &    |- F/_ y A   &    |- F/_ z A   &    |- F/_ y B   &    |- F/_ z B   &    |- F/_ z C   &    |- F/ x ps   &    |- F/ y ch   &    |- F/ z th   &    |- ( x = A -> ( ph <-> ps ) )   &    |- ( y = B -> ( ps <-> ch ) )   &    |- ( z = C -> ( ch <-> th ) )   &    |- ( ( x e. R /\ y e. S /\ z e. T ) -> ph )   =>    |- ( ( A e. R /\ B e. S /\ C e. T ) -> th )
Theorem	vtocl3ga 3186*	Implicit substitution of 3 classes for 3 setvar variables. (Contributed by NM, 20-Aug-1995.)
|- ( x = A -> ( ph <-> ps ) )   &    |- ( y = B -> ( ps <-> ch ) )   &    |- ( z = C -> ( ch <-> th ) )   &    |- ( ( x e. D /\ y e. R /\ z e. S ) -> ph )   =>    |- ( ( A e. D /\ B e. R /\ C e. S ) -> th )
Theorem	vtocl4g 3187*	Implicit substitution of 4 classes for 4 setvar variables. (Contributed by AV, 22-Jan-2019.)
|- ( x = A -> ( ph <-> ps ) )   &    |- ( y = B -> ( ps <-> ch ) )   &    |- ( z = C -> ( ch <-> rh ) )   &    |- ( w = D -> ( rh <-> th ) )   &    |- ph   =>    |- ( ( ( A e. Q /\ B e. R ) /\ ( C e. S /\ D e. T ) ) -> th )
Theorem	vtocl4ga 3188*	Implicit substitution of 4 classes for 4 setvar variables. (Contributed by AV, 22-Jan-2019.)
|- ( x = A -> ( ph <-> ps ) )   &    |- ( y = B -> ( ps <-> ch ) )   &    |- ( z = C -> ( ch <-> rh ) )   &    |- ( w = D -> ( rh <-> th ) )   &    |- ( ( ( x e. Q /\ y e. R ) /\ ( z e. S /\ w e. T ) ) -> ph )   =>    |- ( ( ( A e. Q /\ B e. R ) /\ ( C e. S /\ D e. T ) ) -> th )
Theorem	vtocleg 3189*	Implicit substitution of a class for a setvar variable. (Contributed by NM, 21-Jun-1993.)
|- ( x = A -> ph )   =>    |- ( A e. V -> ph )
Theorem	vtoclegft 3190*	Implicit substitution of a class for a setvar variable. (Closed theorem version of vtoclef 3191.) (Contributed by NM, 7-Nov-2005.) (Revised by Mario Carneiro, 11-Oct-2016.)
|- ( ( A e. B /\ F/ x ph /\ A. x ( x = A -> ph ) ) -> ph )
Theorem	vtoclef 3191*	Implicit substitution of a class for a setvar variable. (Contributed by NM, 18-Aug-1993.)
|- F/ x ph   &    |- A e. _V   &    |- ( x = A -> ph )   =>    |- ph
Theorem	vtocle 3192*	Implicit substitution of a class for a setvar variable. (Contributed by NM, 9-Sep-1993.)
|- A e. _V   &    |- ( x = A -> ph )   =>    |- ph
Theorem	vtoclri 3193*	Implicit substitution of a class for a setvar variable. (Contributed by NM, 21-Nov-1994.)
|- ( x = A -> ( ph <-> ps ) )   &    |- A. x e. B ph   =>    |- ( A e. B -> ps )
Theorem	spcimgft 3194	A closed version of spcimgf 3196. (Contributed by Mario Carneiro, 4-Jan-2017.)
|- F/ x ps   &    |- F/_ x A   =>    |- ( A. x ( x = A -> ( ph -> ps ) ) -> ( A e. B -> ( A. x ph -> ps ) ) )
Theorem	spcgft 3195	A closed version of spcgf 3198. (Contributed by Andrew Salmon, 6-Jun-2011.) (Revised by Mario Carneiro, 4-Jan-2017.)
|- F/ x ps   &    |- F/_ x A   =>    |- ( A. x ( x = A -> ( ph <-> ps ) ) -> ( A e. B -> ( A. x ph -> ps ) ) )
Theorem	spcimgf 3196	Rule of specialization, using implicit substitution. Compare Theorem 7.3 of [Quine] p. 44. (Contributed by Mario Carneiro, 4-Jan-2017.)
|- F/_ x A   &    |- F/ x ps   &    |- ( x = A -> ( ph -> ps ) )   =>    |- ( A e. V -> ( A. x ph -> ps ) )
Theorem	spcimegf 3197	Existential specialization, using implicit substitution. (Contributed by Mario Carneiro, 4-Jan-2017.)
|- F/_ x A   &    |- F/ x ps   &    |- ( x = A -> ( ps -> ph ) )   =>    |- ( A e. V -> ( ps -> E. x ph ) )
Theorem	spcgf 3198	Rule of specialization, using implicit substitution. Compare Theorem 7.3 of [Quine] p. 44. (Contributed by NM, 2-Feb-1997.) (Revised by Andrew Salmon, 12-Aug-2011.)
|- F/_ x A   &    |- F/ x ps   &    |- ( x = A -> ( ph <-> ps ) )   =>    |- ( A e. V -> ( A. x ph -> ps ) )
Theorem	spcegf 3199	Existential specialization, using implicit substitution. (Contributed by NM, 2-Feb-1997.)
|- F/_ x A   &    |- F/ x ps   &    |- ( x = A -> ( ph <-> ps ) )   =>    |- ( A e. V -> ( ps -> E. x ph ) )
Theorem	spcimdv 3200*	Restricted specialization, using implicit substitution. (Contributed by Mario Carneiro, 4-Jan-2017.)
|- ( ph -> A e. B )   &    |- ( ( ph /\ x = A ) -> ( ps -> ch ) )   =>    |- ( ph -> ( A. x ps -> ch ) )