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is a subclass of every class, and any class is a subclass of itself. But additionally, every class is a subclass of the class of all sets. Accordingly, the subclass relation makes the collection of all classes into a
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in the collection of all classes. (Of course, the collection of all classes is something larger than even a class!)
94:, which the subset relation does not do for the collection of all sets. Instead, the collection of all sets is an
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contained in some other set. One may also call this "inclusion of classes".
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contained in some other class in the same way that a
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121:. Dover Publications Inc. p. 240.
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162:. You can help Knowledge (XXG) by
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20:and its applications throughout
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115:Charles C.Pinter (2013).
82:must then also be a set.
43:That is, given classes
158:-related article is a
78:essentially says that
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85:As with subsets, the
118:A Book of Set Theory
66:is also a member of
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214:Set theory stubs
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80:A
72:B
68:B
64:A
57:B
53:A
49:B
45:A
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