1.Previous
3.Next

example of a primitive notion. As Mary Tiles writes: [The] 'definition' of 'set' is less a definition than an attempt at explication of something which is being given the status of a primitive, undefined, term. As evidence, she quotes Felix Hausdorff: "A set is formed by the grouping together of single objects into a whole. A set is a plurality thought of as a unit."
* Naive set theory: The empty set

1.Previous
3.Next