diff --git a/doc/index.html b/doc/index.html
index 1df4b4e4ea..5f2b76267c 100644
--- a/doc/index.html
+++ b/doc/index.html
@@ -183,8 +183,8 @@ make install</pre>
 
       <p>
         <i>
-          But what about multiple-processor concurrency? Threads are
-          necessary to scale programs to multi-core computers.
+        But what about multiple-processor concurrency? Aren't threads
+        necessary to scale programs to multi-core computers?
         </i>
         Processes are necessary to scale to multi-core computers, not
         memory-sharing threads. The fundamentals of scalable systems are