===== Arbitrary union =====
==== Set ====
| @#55CCEE: context     | @#55CCEE: $ S\in \mathfrak U $ |
| @#FFBB00: definiendum | @#FFBB00: $ x\in \bigcup S $ |
| @#DDDDDD: range       | @#DDDDDD: $ X\in S $ | 
| @#55EE55: postulate   | @#55EE55: $ \exists X.\ x\in X $ |

==== Discussion ====
=== Reference ===
Wikipedia: [[http://en.wikipedia.org/wiki/Union_%28set_theory%29|Arbitrary union]]
==== Parents ====
=== Element of ===
[[Set universe]]
=== Context* ===
[[Set universe]]