--- a/HelloForge/helloforge/main.py
+++ b/HelloForge/helloforge/main.py
@@ -161,15 +161,15 @@
             return None
 
     @expose('helloforge.templates.page_view')
-    @validate(dict(version=V.Int()))
+    @validate(dict(version=V.Int(if_empty=None)))
     def index(self, version=None):
         require(has_artifact_access('read', self.page))
         page = self.get_version(version)
         if page is None:
             if version: redirect('.?version=%d' % (version-1))
             else: redirect('.')
-        cur = page.version - 1
-        if cur > 0: prev = cur-1
+        cur = page.version
+        if cur > 1: prev = cur-1
         else: prev = None
         next = cur+1
         return dict(page=page,
@@ -194,8 +194,6 @@
         require(has_artifact_access('read', self.page))
         p1 = self.get_version(int(v1))
         p2 = self.get_version(int(v2))
-        p1.version -= 1
-        p2.version -= 1
         t1 = p1.text
         t2 = p2.text
         differ = difflib.SequenceMatcher(None, p1.text, p2.text)