diff --git a/main/nonergodic.tex b/main/nonergodic.tex
index ff3a554..42a982f 100644
--- a/main/nonergodic.tex
+++ b/main/nonergodic.tex
@@ -87,7 +87,7 @@ the truncated  St. Petersburg paradox
 is non-ergodic between non-absorbing states.
 
 \subsection{A sufficient condition for non-ergodicity between non-absorbing states}
-Based on the truncated  St. Petersburg paradox, 
+By observing the truncated  St. Petersburg paradox, 
 it is easy to provide a sufficient condition for non-ergodicity between non-absorbing states.
 \begin{theorem}[A sufficient condition for non-ergodicity between non-absorbing states]
 Given a Markov chain with absorbing states,