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<record version="4" id="3241">
 <title>chain condition</title>
 <name>ChainCondition</name>
 <created>2002-07-30 21:47:50</created>
 <modified>2006-06-23 10:02:13</modified>
 <type>Definition</type>
 <creator id="455" name="Henry"/>
 <author id="455" name="Henry"/>
 <classification>
	<category scheme="msc" code="03E35"/>
 </classification>
 <defines>
	<concept>chain condition</concept>
	<concept>countable chain condition</concept>
	<concept>$\kappa$-chain condition</concept>
	<concept>c.c.c.</concept>
	<concept>ccc</concept>
 </defines>
 <related>
	<object name="PartialOrder"/>
	<object name="PartialOrderWithChainConditionDoesNotCollapseCardinals"/>
 </related>
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 <content>A partial order $P$ satisfies the \emph{$\kappa$-chain condition} if for any $S\subseteq P$ with $|S|=\kappa$ then there exist distinct $x,y\in S$ and some $p$ such that $p\leq x$ and $p\leq y$.

If $\kappa=\aleph_1$ then $P$ is said to satisfy the \emph{countable chain condition} (c.c.c.)</content>
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