Once the famous ghair muqallid, Talibur Rahman said to Hazrat Maulana Muhammad Ameen Safdar (رحمهما الله):

“Look, you believe in the Quran and Hadith and we believe in the Quran and Hadith. We both agree that the Quran and Hadith are sources of evidence. However, we disagree in Ijma (consensus of the scholars) and Qiyas (analogy) being sources of evidence. Therefore let us use the agreed upon sources of evidence (in our debate) and leave the mukhtalaf feeh (disputed) sources of evidence.”

Hazrat Maulana immediately replied:

“This fabricated principle of yours is unsound. Because we agree on certain issues does not mean one group should leave his principles. If a Christian was to say to you, we both believe in the Bible but disagree in the Quran. Will you use the agreed upon source of evidence, Bible in the debate and leave the disputed source of evidence, the Quran?”

The ghair muqallid was dumbfounded by this answer.

Principle:

In a debate, never abandon your source of evidence simply because the next party does not agree in it being a source of evidence.