A quick comment on comments
Readers may notice that several negative comments have been posted to the site today.
It is not GPW’s policy to censor comments. We do, however, attract a good deal of spam comments. We use a software package to “catch” those spam comments, but sometimes legitimate comments get “caught” too, so we must review the spam to release those comments.
If you have attempted to post a comment, and see that it did not get published, please send a note to the contact address so we can find the comment and get it out of the spam queue.

There’s a good article on ad hominem arguments over at Op Ed News:
http://www.opednews.com/articles/1/Ad-Hominem-Attacks-by-Rady-Ananda-090106-173.html
Executive summary: The relevant question is not who makes the argument, but whether the argument is valid.