Allow me to reframe F.O.'s belief in civil and rational discourse in this post. It converges with my own aims; call it confirmation bias.
In any discussion,
"... the development of a critical approach to our own understanding of, as well as to existing knowledge about, the world is fundamental for students and educators alike."
- Anonymous
Let's ignore the part about "students and educators" for the moment to talk about critical reflection. Critical reflection is one of the higher-order cognitive skills of mankind, and like other such intelligences, is prized both for itself as well as for its practical usefulness.
In terms of style, critically reflective discussion can go one of two ways: circularity, and balance.
Valuing critical reflection for itself, i.e. ‘understanding of the world’ as in the quote, does not convey the world's impact upon our own understanding as in the ‘person-in-environment’ perspective, and therefore has its limitations in real life. This refers to people who hold their opinions very firmly and refuse to budge from them.
One could think of the discussion between two (or more) such "critically reflective" people as a circle on a plane. They will endlessly be at cross-purposes. Now hold the image of circle on plane firmly in your mind for later comparison.
What distinguishes circularity from balance?
Balance is where discussion moves away from going round in circles to going somewhere else. You have two (or more) people who hold their opinions firmly but can be budged due to rational or emotional persuasion, or what F.O. calls civil and rational discourse.
So instead of limiting themselves to two dimensions on the flat plane (you say to-may-to, i say to-mah-to), it is possible that they still go round in circles but in a screw sort of symmetry instead.
This gives a whole new meaning to the phrase "screw you".
But more seriously, screw-type critically reflective discussions takes you places; if you have a preference for exploring circles in flat planes, screw-type discussions gives you a wonderful variety of circles to play with. And if you have the other preference for learning from others (balance, or screw-type discussions), civil and rational discourse is a great way to gradually do so without too much cognitive dissonance occurring.
These are possibilities.
(Update 02/01/07: While searching for something else, I have just come across one of Catherine Lim's articles in which she says "One gets the surreal feeling that everyone seems trapped in a Samuel Beckett-like circularity that nobody knows how to break out of". How apropos. Link here: 'Utopia or dystopia' ST 10 May 2005)