diff --git a/book/src/part1/chapter1/1.7.md b/book/src/part1/chapter1/1.7.md
index 8337b86..e024f20 100644
--- a/book/src/part1/chapter1/1.7.md
+++ b/book/src/part1/chapter1/1.7.md
@@ -1,4 +1,4 @@
-### 1.6 The appearance of appearance
+### 1.7 The appearance of appearance
 
 
 ----