# Difference between revisions of "Talk:Reflecting ordinal"

A property that seems important about reflection is that for any $\Pi_n$-definable class $X$, being $\Pi_n$-reflection on Ord and in $X$ implies being $\Pi_n$-reflecting on $X$. For example, if an ordinal is $\Pi_2$-reflecting and a limit of admissibles, it's also $\Pi_2$-reflecting on the class of limits of admissibles. But I don't know how to add this to the article, since although I've seen a proof I've never seen a published proof C7X (talk) 22:10, 30 May 2022 (PDT)