Evaluating traditions through intelligence, not hearsay
Nahj al-Balāgha|Volume 1|Book 3|Chapter 98
٩٨. وَقَالَ (عليه السلام): اعْقِلُوا الْخَبَرَ إِذَا سَمِعْتُمُوهُ عَقْلَ رِعَايَةٍ لَا عَقْلَ رِوَايَةٍ فَإِنَّ رُوَاةَ الْعِلْمِ كَثِيرٌ وَرُعَاتَهُ قَلِيلٌ.
98. Amīr al-mu’minīn, peace be upon him, said: When you hear a tradition test it according to the criterion of intelligence not that of mere hearing, because relaters of knowledge are numerous but those who guard it are few.