Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
bayhaqi:16388Abū Saʿīd al-Ṣayrafī > Abū al-ʿAbbās al-Aṣam Nbʾ al-Rabīʿ > al-Shāfiʿī > Baʿḍuhum Faʾin Yaḥyá b. Saʿīd > from al-Amr al-Qadīm

[Machine] To rationalize, the rational person should take into consideration the third, ascending measurement. We said that the ancient (opinion) could be one that is followed and its statement is binding, and it could be from the rulers who are not to be followed and their statement is not binding. So, do we abandon certainty that the Prophet ﷺ decided upon half the value of the blood money with a conjecture?  

البيهقي:١٦٣٨٨أَخْبَرَنَا أَبُو سَعِيدٍ الصَّيْرَفِيُّ ثنا أَبُو الْعَبَّاسِ الْأَصَمُّ أنبأ الرَّبِيعُ قَالَ قَالَ الشَّافِعِيُّ قَالَ بَعْضُهُمْ فَإِنَّ يَحْيَى بْنَ سَعِيدٍ قَالَ مِنَ الْأَمْرِ الْقَدِيمِ

أَنْ تَعْقِلَ الْعَاقِلَةُ الثُّلُثَ فَصَاعِدًا قُلْنَا الْقَدِيمُ قَدْ يَكُونُ مِمَّنْ يُقْتَدَى بِهِ وَيَلْزَمُ قَوْلُهُ وَيَكُونُ مِنَ الْوُلَاةِ الَّذِينَ لَا يُقْتَدَى بِهِمْ وَلَا يَلْزَمُ قَوْلُهُمْ أَفَنَتْرُكُ الْيَقِينَ أَنَّ النَّبِيَّ ﷺ قَضَى بِنِصْفِ عُشْرِ الدِّيَةِ عَلَى الْعَاقِلَةِ بِظَنٍّ؟