Every subset equal to original set?Is the void set (∅) a proper subset of every set?Set theory: difference...

When was drinking water recognized as crucial in marathon running?

Sometimes a banana is just a banana

Should we avoid writing fiction about historical events without extensive research?

How can I create a Table like this in Latex?

Pure Functions: Does "No Side Effects" Imply "Always Same Output, Given Same Input"?

What could trigger powerful quakes on icy world?

Citing contemporaneous (interlaced?) preprints

Are paired adjectives bad style?

At what level can a party fight a mimic?

Non-Italian European mafias in USA?

If nine coins are tossed, what is the probability that the number of heads is even?

Reason why dimensional travelling would be restricted

Is there a frame of reference in which I was born before I was conceived?

Every subset equal to original set?

I can't die. Who am I?

In Adventurer's League, is it possible to keep the Ring of Winter if you manage to acquire it in the Tomb of Annihilation adventure?

Do higher etale homotopy groups of spectrum of a field always vanish?

Starting index at zero

What does @RC mean in SSDT SQL Server Unit Testing?

How do you say "powers of ten"?

Is there a full canon version of Tyrion's jackass/honeycomb joke?

If a set is open, does that imply that it has no boundary points?

Why do phishing e-mails use faked e-mail addresses instead of the real one?

For a 1-action spell, do I need to take a turn to ready the spell before I can cast it, or can I cast it immediately?



Every subset equal to original set?


Is the void set (∅) a proper subset of every set?Set theory: difference between belong/contained and includes/subset?Proving every infinite set is a subset of some denumerable set and vice versaIf the empty set is a subset of every set, why isn't ${emptyset,{a}}={{a}}$?What is the reason behind calling $emptyset$ improper subset of any non-empty set.?Can subset of a countable set be uncountable?Set Theory Subset QuestionIs every empty set equal?Why a set that is subset/equal to infinite set isn't infinite? (by definition)Why the empty set is a subset of every set?













1












$begingroup$


Is there any set whose every subset is equal to the set itself? It seems like this isn't possible, but maybe something similar is possible.










share|cite|improve this question









$endgroup$

















    1












    $begingroup$


    Is there any set whose every subset is equal to the set itself? It seems like this isn't possible, but maybe something similar is possible.










    share|cite|improve this question









    $endgroup$















      1












      1








      1





      $begingroup$


      Is there any set whose every subset is equal to the set itself? It seems like this isn't possible, but maybe something similar is possible.










      share|cite|improve this question









      $endgroup$




      Is there any set whose every subset is equal to the set itself? It seems like this isn't possible, but maybe something similar is possible.







      elementary-set-theory






      share|cite|improve this question













      share|cite|improve this question











      share|cite|improve this question




      share|cite|improve this question










      asked 31 mins ago









      lthompsonlthompson

      1169




      1169






















          2 Answers
          2






          active

          oldest

          votes


















          3












          $begingroup$

          In standard foundations (by which I mean ZF, or ZFC) the empty set works:
          If $Ssubset emptyset$, then $S = emptyset$.



          If you wish to do so otherwise, you’d violate the Axiom of Extensionality.






          share|cite|improve this answer









          $endgroup$





















            3












            $begingroup$

            The empty set has only itself as a subset. This is the only example because every set has the empty set as a subset.






            share|cite|improve this answer









            $endgroup$













              Your Answer





              StackExchange.ifUsing("editor", function () {
              return StackExchange.using("mathjaxEditing", function () {
              StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
              StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
              });
              });
              }, "mathjax-editing");

              StackExchange.ready(function() {
              var channelOptions = {
              tags: "".split(" "),
              id: "69"
              };
              initTagRenderer("".split(" "), "".split(" "), channelOptions);

              StackExchange.using("externalEditor", function() {
              // Have to fire editor after snippets, if snippets enabled
              if (StackExchange.settings.snippets.snippetsEnabled) {
              StackExchange.using("snippets", function() {
              createEditor();
              });
              }
              else {
              createEditor();
              }
              });

              function createEditor() {
              StackExchange.prepareEditor({
              heartbeatType: 'answer',
              autoActivateHeartbeat: false,
              convertImagesToLinks: true,
              noModals: true,
              showLowRepImageUploadWarning: true,
              reputationToPostImages: 10,
              bindNavPrevention: true,
              postfix: "",
              imageUploader: {
              brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
              contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
              allowUrls: true
              },
              noCode: true, onDemand: true,
              discardSelector: ".discard-answer"
              ,immediatelyShowMarkdownHelp:true
              });


              }
              });














              draft saved

              draft discarded


















              StackExchange.ready(
              function () {
              StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3137096%2fevery-subset-equal-to-original-set%23new-answer', 'question_page');
              }
              );

              Post as a guest















              Required, but never shown

























              2 Answers
              2






              active

              oldest

              votes








              2 Answers
              2






              active

              oldest

              votes









              active

              oldest

              votes






              active

              oldest

              votes









              3












              $begingroup$

              In standard foundations (by which I mean ZF, or ZFC) the empty set works:
              If $Ssubset emptyset$, then $S = emptyset$.



              If you wish to do so otherwise, you’d violate the Axiom of Extensionality.






              share|cite|improve this answer









              $endgroup$


















                3












                $begingroup$

                In standard foundations (by which I mean ZF, or ZFC) the empty set works:
                If $Ssubset emptyset$, then $S = emptyset$.



                If you wish to do so otherwise, you’d violate the Axiom of Extensionality.






                share|cite|improve this answer









                $endgroup$
















                  3












                  3








                  3





                  $begingroup$

                  In standard foundations (by which I mean ZF, or ZFC) the empty set works:
                  If $Ssubset emptyset$, then $S = emptyset$.



                  If you wish to do so otherwise, you’d violate the Axiom of Extensionality.






                  share|cite|improve this answer









                  $endgroup$



                  In standard foundations (by which I mean ZF, or ZFC) the empty set works:
                  If $Ssubset emptyset$, then $S = emptyset$.



                  If you wish to do so otherwise, you’d violate the Axiom of Extensionality.







                  share|cite|improve this answer












                  share|cite|improve this answer



                  share|cite|improve this answer










                  answered 25 mins ago









                  user458276user458276

                  743212




                  743212























                      3












                      $begingroup$

                      The empty set has only itself as a subset. This is the only example because every set has the empty set as a subset.






                      share|cite|improve this answer









                      $endgroup$


















                        3












                        $begingroup$

                        The empty set has only itself as a subset. This is the only example because every set has the empty set as a subset.






                        share|cite|improve this answer









                        $endgroup$
















                          3












                          3








                          3





                          $begingroup$

                          The empty set has only itself as a subset. This is the only example because every set has the empty set as a subset.






                          share|cite|improve this answer









                          $endgroup$



                          The empty set has only itself as a subset. This is the only example because every set has the empty set as a subset.







                          share|cite|improve this answer












                          share|cite|improve this answer



                          share|cite|improve this answer










                          answered 24 mins ago









                          Ross MillikanRoss Millikan

                          298k24200373




                          298k24200373






























                              draft saved

                              draft discarded




















































                              Thanks for contributing an answer to Mathematics Stack Exchange!


                              • Please be sure to answer the question. Provide details and share your research!

                              But avoid



                              • Asking for help, clarification, or responding to other answers.

                              • Making statements based on opinion; back them up with references or personal experience.


                              Use MathJax to format equations. MathJax reference.


                              To learn more, see our tips on writing great answers.




                              draft saved


                              draft discarded














                              StackExchange.ready(
                              function () {
                              StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3137096%2fevery-subset-equal-to-original-set%23new-answer', 'question_page');
                              }
                              );

                              Post as a guest















                              Required, but never shown





















































                              Required, but never shown














                              Required, but never shown












                              Required, but never shown







                              Required, but never shown

































                              Required, but never shown














                              Required, but never shown












                              Required, but never shown







                              Required, but never shown







                              Popular posts from this blog

                              Fairchild Swearingen Metro Inhaltsverzeichnis Geschichte | Innenausstattung | Nutzung | Zwischenfälle...

                              Pilgersdorf Inhaltsverzeichnis Geografie | Geschichte | Bevölkerungsentwicklung | Politik | Kultur...

                              Marineschifffahrtleitung Inhaltsverzeichnis Geschichte | Heutige Organisation der NATO | Nationale und...