Here are the basic rules for using this blog as a discussion forum.
1) If you are starting a new topic/idea/quote/link/whatever, then create a new post. For those of you new to Blogger, here's how you do it:
a)go to blogger.com
b)log in - this should take you to your "dashboard"
c)on your dashboard, locate this blog's title and click on "new post"
d)use the editor to write something, then click "publish post"
2) If you are responding to someone else's topic/idea/quote/link/whatever, then use the "comment" option, either by clicking on the post title or the timestamp or the comments link, all of which will give you the option to write something, either at the bottom of the page or on the side of the page.