Statement List for Metamath Proof Explorer - 2801-2900 - Page 29 of 107
| Type | Label | Description |
| Statement |
| |
| Theorem | mosubopt 2801 |
"At most one" remains true inside ordered pair quantification.
|
                    |
| |
| Theorem | mosubop 2802 |
"At most one" remains true inside ordered pair quantification.
|
              |
| |
| Theorem | euop2 2803 |
Transfer existential uniqueness to second member of an ordered pair.
|
              |
| |
| Theorem | opthwiener 2804 |
Justification theorem for the ordered pair definition in Norbert Wiener,
"A simplification of the logic of relations," Proc. of the
Cambridge
Philos. Soc., 1914, vol. 17, pp.387-390. It is also shown as a
definition in [Enderton] p. 36 and as
Exercise 4.8(b) of [Mendelson]
p. 230. It is meaningful only for classes that exist as sets (i.e.
are not proper classes). See df-op 2412 for other ordered pair
definitions.
|
            
                |
| |
| Theorem | uniop 2805 |
The union of an ordered pair. Theorem 65 of [Suppes] p. 39.
|
   
    |
| |
| Theorem | uniopel 2806 |
Ordered pair membership is inherited by class union.
|
           |
| |
| Ordered-pair class abstractions (cont.) |
| |
| Theorem | opabid 2807 |
The law of concretion. Special case of Theorem 9.5 of [Quine] p. 61.
|
           |
| |
| Theorem | elopab 2808 |
Membership in a class abstraction of pairs.
|
                 |
| |
| Theorem | hbopab 2809 |
Bound-variable hypothesis builder for class abstraction.
|
                  |
| |
| Theorem | hbopab1 2810 |
The first abstraction variable in an ordered-pair class abstraction
(class builder) is effectively not free.
|
              |
| |
| Theorem | hbopab2 2811 |
The second abstraction variable in an ordered-pair class abstraction
(class builder) is effectively not free.
|
              |
| |
| Theorem | opabsb 2812 |
The law of concretion in terms of substitutions.
|
           ![]](rbrack.gif) 
 ![]](rbrack.gif)   |
| |
| Theorem | brabsb 2813 |
The law of concretion in terms of substitutions.
|
  
       ![]](rbrack.gif)   ![]](rbrack.gif)   |
| |
| Theorem | opelopabg 2814 |
The law of concretion. Theorem 9.5 of [Quine]
p. 61.
|
                       |
| |
| Theorem | brabg 2815 |
The law of concretion for a binary relation.
|
                      |
| |
| Theorem | opelopab2 2816 |
Ordered pair membership in an ordered pair class abstraction.
|
                    

     |
| |
| Theorem | opelopab 2817 |
The law of concretion. Theorem 9.5 of [Quine]
p. 61.
|
    

        
    |
| |
| Theorem | brab 2818 |
The law of concretion for a binary relation.
|
    

    
       |
| |
| Theorem | ssopab2 2819 |
Equivalence of ordered pair abstraction subclass and implication.
|
     
  
          |
| |
| Theorem | ssopab2i 2820 |
Inference of ordered pair abstraction subclass from implication.
|
             |
| |
| Theorem | opabn0 2821 |
Non-empty ordered pair class abstraction.
|
     
      |
| |
| Power
class of union and intersection |
| |
| Theorem | pwin 2822 |
The power class of the intersection of two classes is the intersection
of their power classes. Exercise 4.12(j) of [Mendelson] p. 235.
|
        |
| |
| Theorem | pwunss 2823 |
The power class of the union of two classes includes the union of their
power classes. Exercise 4.12(k) of [Mendelson] p. 235.
|
     
  |
| |
| Theorem | pwssun 2824 |
The power class of the union of two classes is a subset of the union of
their power classes, iff one class is a subclass of the other. Exercise
4.12(l) of [Mendelson] p. 235.
|
 
     
    |
| |
| Theorem | pwundif 2825 |
Break up the power class of a union into a union of smaller classes.
|
             |
| |
| Theorem | pwun 2826 |
The power class of the union of two classes equals the union of their
power classes, iff one class is a subclass of the other. Part of
Exercise 7(b) of [Enderton] p. 28.
|
 
          |
| |
| Epsilon and identity relations |
| |
| Syntax | cep 2827 |
Extend class notation to include the epsilon relation.
|
 |
| |
| Syntax | cid 2828 |
Extend the definition of a class to include identity relation.
|
 |
| |
| Definition | df-eprel 2829 |
Define the epsilon relation. Similar to Definition 6.22 of
[TakeutiZaring] p. 30.
|
  

  |
| |
| Theorem | epelc 2830 |
The epsilon relation and the membership relation are the same.
|
     |
| |
| Theorem | epel 2831 |
The epsilon relation and the membership relation are the same.
|
     |
| |
| Definition | df-id 2832 |
Define the identity relation. Definition 9.15 of [Quine] p. 64.
|
  

  |
| |
| Theorem | ideqgOLD 2833 |
For sets, the identity relation is the same as equality.
|
         |
| |
| Theorem | dfid3 2834 |
A stronger version of df-id 2832 that doesn't require and to be
distinct. Ordinarily, we wouldn't use this as a definition, since
non-distinct dummy variables would make soundness verification more
difficult (as the proof here shows). The proof can be instructive in
showing how distinct variable requirements may be eliminated, a task
that is not necessarily obvious.
|
  

  |
| |
| Theorem | dfid2 2835 |
Alternate definition of the identity relation.
|
  

  |
| |
| Theorem | ideqOLD 2836 |
For sets, the identity relation is the same as equality.
|
     |
| |
| Partial and complete ordering |
| |
| Syntax | wpo 2837 |
Extend wff notation to include the strict partial ordering predicate.
Read: ' is a
partial order on .'
|
 |
| |
| Syntax | wor 2838 |
Extend wff notation to include the strict complete ordering predicate.
Read: ' orders
.'
|
 |
| |
| Definition | df-po 2839 |
Define a strict partial order relation. Definition of [Enderton]
p. 168.
|
 
  
 
             |
| |
| Theorem | poss 2840 |
Subset theorem for the partial ordering predicate.
|
     |
| |
| Theorem | poeq1 2841 |
Equality theorem for partial ordering predicate.
|
     |
| |
| Theorem | poeq2 2842 |
Equality theorem for partial ordering predicate.
|
     |
| |
| Theorem | pocl 2843 |
Properties of partial order relation in class notation.
|
                     |
| |
| Theorem | poirr 2844 |
A partial order relation is irreflexive.
|
 
     |
| |
| Theorem | potr 2845 |
A partial order relation is a transitive relation.
|
 

              |
| |
| Theorem | po2nr 2846 |
A partial order relation has no 2-cycle loops.
|
 

          |
| |
| Theorem | po3nr 2847 |
A partial order relation has no 3-cycle loops.
|
 

            |
| |
| Theorem | po0 2848 |
Any relation is a partial ordering of the empty set.
|
 |
| |
| Definition | df-so 2849 |
Define a strict complete (linear) order relation.
|
 
           |
| |
| Theorem | sopo 2850 |
A strict linear order is a strict partial order.
|
   |
| |
| Theorem | soss 2851 |
Subset theorem for the strict ordering predicate.
|
     |
| |
| Theorem | soeq1 2852 |
Equality theorem for the strict ordering predicate.
|
     |
| |
| Theorem | soeq2 2853 |
Equality theorem for the strict ordering predicate.
|
     |
| |
| Theorem | sonr 2854 |
A strict order relation is irreflexive.
|
 
     |
| |
| Theorem | sotr 2855 |
A strict order relation is a transitive relation.
|
 

              |
| |
| Theorem | solin 2856 |
A strict order relation is linear (satisfies trichotomy).
|
 

          |
| |
| Theorem | so2nr 2857 |
A strict order relation has no 2-cycle loops.
|
 

          |
| |
| Theorem | so3nr 2858 |
A strict order relation has no 3-cycle loops.
|
 

            |
| |
| Theorem | sotric 2859 |
A strict order relation satisfies strict trichotomy.
|
 

      |