After running:
pacman -Su

I ran:
pacman -Sy scribes

When I tried to run scribes, I got the following error message:
$ scribes
Traceback (most recent call last):
File "/usr/bin/scribes", line 94, in ?
from Scribes.main import main
File "/usr/lib/python2.4/site-packages/Scribes/main.py", line 51, in ?
from fileloader import FileLoader
File "/usr/lib/python2.4/site-packages/Scribes/fileloader.py", line 47, in ?
from syntax import syntax_highlight
File "/usr/lib/python2.4/site-packages/Scribes/syntax.py", line 34, in ?
from gtksourceview import SourceLanguagesManager, SourceTagStyle
ImportError: libgtksourceview-1.0.so.0: cannot open shared object file: No such file or directory

After a few minutes on Google, I found libgtksourceview-1.0.so.0 is part of gtksourceview

$ pacman -Q gtksourceview
Package "gtksourceview" was not found.

$ pacman -Sy gtksourceview

This time, when I tried to run scribes, I got another error message:
$ scribes
Traceback (most recent call last):
File "/usr/bin/scribes", line 94, in ?
from Scribes.main import main
File "/usr/lib/python2.4/site-packages/Scribes/main.py", line 52, in ?
from editor import Editor
File "/usr/lib/python2.4/site-packages/Scribes/editor.py", line 51, in ?
from gtkspell import Spell
ImportError: No module named gtkspell

After a few more minutes on Google, I found the missing module was part of gnome-python-extras

$ pacman -Q gnome-python-extras
Package "gnome-python-extras" was not found.

$ pacman -Sy gnome-python-extras

This time when I ran scribes, the GUI popped up, and seemed functional at first glance. However, clicking on the floatation ring icon produced the following error message instead of providing help:
$ scribes (click on floatation ring icon)
Traceback (most recent call last):
File "/usr/lib/python2.4/site-packages/Scribes/actions.py", line 373, in help_cb
launch_user_guide(editor)
File "/usr/lib/python2.4/site-packages/Scribes/help.py", line 49, in launch_user_guide
help_display("/scribes.xml")
gobject.GError: There was an error launching the default action command associated with this location.

I had to add /opt/gnome/bin to PATH in my bashrc to fix this problem.

It appears to me that gtksourceview and gnome-python-extras need to be added to the scribes package dependencies. It also appears to me that the installation script should warn that /opt/gnome/bin needs to be in the user's path. The scribes binary is in /usr/bin, which is in the default Arch path. However, the floatation ring icon calls yelp, which is in /opt/gnome/bin, not in the default Arch path.