September 2015
Beginner
596 pages
18h 33m
English
Appendix A
A set is a Many that allows itself to be thought of as a One.
– Georg Cantor
Amazon should put their cloud in a cloud, so the cloud will have the redundancy of the cloud.
– @dowens
A set is a collection of objects. The objects can be anything: numbers, people, cats, courses, even other sets! The language of sets allows us to talk precisely about events. If S is a set, then the notation x ∈ S indicates that x is an element or member of the set S (and x ∉ S indicates that x is not in S). We can think of the set as a club, with precisely defined criteria for membership. For example: