# Category:Class Theory

Jump to navigation
Jump to search

This category contains results about Class Theory.

Definitions specific to this category can be found in Definitions/Class Theory.

**Class theory** is an extension of set theory which allows the creation of collections that are not sets by classes.

## Subcategories

This category has the following 34 subcategories, out of 34 total.

### A

- Axiom of Infinity (1 P)
- Axiom of Pairing (5 P)

### B

- Basic Universe (6 P)

### C

- Class Difference (empty)
- Class Intersection (4 P)
- Class Mappings (13 P)
- Class Theory Work in Progress (58 P)

### D

- Doubleton Classes (4 P)

### E

- Empty Class (5 P)

### F

- Finite Classes (2 P)

### G

- Gödel-Bernays Class Theory (6 P)

### I

### M

### N

- Nests (1 P)
- Not Every Class is a Set (3 P)

### O

### R

- Relational Closures (6 P)

### S

- Subclasses (1 P)
- Supercomplete Classes (2 P)

### T

### U

- Universal Class (3 P)
- Universal Class is Proper (4 P)

### V

- Von Neumann Hierarchy (13 P)

### Z

## Pages in category "Class Theory"

The following 33 pages are in this category, out of 33 total.

### C

- Cardinal Class is Proper Class
- Cartesian Product with Proper Class is Proper Class
- Class Equal to All its Elements
- Class Equality is Reflexive
- Class Equality is Symmetric
- Class Equality is Transitive
- Class has Subclass which is not Element
- Class is Not Element of Itself
- Class is Transitive iff Union is Subset
- Collection of Sets Equivalent to Set Containing Empty Set is Proper Class