I may have to dissagree. though a logical discussion of ideas is a great way to further your own knowledge and make positive changes, I don'tthink that is what the saying is talking about. I think it is more about contention. haven't you ever been talking to someone who sounds more like a chiuauaha than a person? who is arguing either to establish his position in the group or to defend a undefendable position than because he feels that his opinion is valid?

Lao Tsu said - "he who knows, does not speak, he who speaks does not know"