Excerpted from "Islamic Principles and Rules of Debate"
"A debate is only justified to unveil truth, so that the more knowledgeable should impart knowledge to the less knowledgeable, and to stimulate a weaker intellect." - adh-Dhahabi
"I never talked with someone but sincerely wished that Allah guard him, protect him from sin and misdeed, and guide him; and I never debated with someone but sincerely wished that we would come upon truth, regardless of whether he or I should be the one to think of it first." - Imam al-Shafi`i
"Cooperation in seeking truth is inherent to religion, but sincerity in the pursuit of truth can be distinguished y certain conditions and signs. A diligent seeker of truth may be compared to one who is looking for his lost camel. It would be immaterial for him if he or another person should be the one to find it. Likewise, a sincere truth-seeker would perceive his partner as a helper rather than an adversary, and would be grateful to him if he should guide him to truth." - Al-Ghazali
If quoting, maintain accuracy; if claiming, provide proof. [An aphorism of Muslim scholars]
"Some scholars used to excuse anyone who disagrees with them in debatable matters, and did not insist that he should accept their view." - Ibn Qudama [Al-Mughni]
"My viewpoint is right, but can be wrong; and my adversary's viewpoint is wrong, but can be right." [An aphorism of Muslim scholars]
"I have never debated with a knowledgeable person but beaten him, and I have never debated with an ignorant person but been beaten by him." - Imam al-Shafi`i
"Let each one of the debaters accept statements of the other party supported with proof. By doing that, he would demonstrate a nobility and self-respect, and he would prove himself to be an acceptor of truth." - Ibn Akeel
"Over-enthusiasm is a mark of corrupted scholars, even when the case they are defending is true. By showing excessive enthusiasm for truth and their contempt of their opponents, the latter would be stimulated to retaliate and react in the same manner. They would be driven to stand for falsehood and to be true to the label attributed to them. If the champions of truth had spoken kindly to them avoiding publicity and humiliation they would have succeeded in winning them over. But as it is, a person who enjoys a place of prestige is strongly inclined to preserve his position by attracting followers, and the only way to that is to boast and to attack or curse adversaries." - Al-Ghazali
"I never debate with someone and he accepts my proof except that I hold him in high esteem, and I never debate with someone and he refuses my proof except that I lose all esteem for him." - Imam al-Shafi`i
"If you sit with scholars, my son, be more interested in listening than in speaking. Learn good listening just as you learn good speaking. Never interrupt a speaker, even if he takes long, until he comes to an end." -Advice of Al-Hasan ibn Ali (radhiallahu `anhu) to his son.
"Learn good listening just as you learn good speaking. To be a good listener, you should give a speaker time until he concludes, not seeming anxious to reply. Have your face and look in the direction of the speaker and try to understand what he says." - Ibn al-Muqaffa`