With Views 2.x, Drupal 6, I've created a taxonomy and have enabled it for a Content Type. I then create some content:
node_1 is associated with term_1 (tid=1)
node_2 is associated with term_2 (tid=2)
node_3 has no term association
I've created a Node View that has an Argument for "Taxonomy: Term ID". In the argument configuration, I enable "Allow multiple terms per argument".
Using the Live Preview for the View, I can pass in arguments. So I pass in "1" and the view shows me node_1. I pass in "2" and the view shows me node_2. I pass in "1+2" and the view shows me node_1 and node_2. This is good.
What I can't figure out is how to pass an argument that will return me just node_3. Is there something I can pass to Arguments that essentially means "no argument"?