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.
Qurʾān Bukhārī Muslim Nasāʾī Abū Dāwūd Tirmidhī Ibn Mājah Mālik Aḥmad Dārimī Ḥākim Ibn Ḥibbān Ṭabarānī Nasāʾī's Kubrá Bayhaqī al-Luʾluʾ wa-al-Marjān Ibn Rajab's Fifty Riyāḍ al-Ṣāliḥīn Aḥmad's Zuhd Suyūṭī
bayhaqi:16082 – Abū Ḥāzim al-Ḥāfiẓ > Abū Aḥmad al-Ḥāfiẓ > Abū al-ʿAbbās Aḥmad b. ʿAbdullāh b. Sābūr al-Daqīqī > Abū Nuʿaym al-Ḥalabī ʿUbayd b. Hishām > Ibrāhīm b. Muḥammad al-Madanī > Ḥusayn b. ʿAbdullāh b. Ṣumayrah from his father from his grandfather > ʿAlī

[Machine] Ali said, "The delusion of the insane and the mistake of the child."  

البيهقي:١٦٠٨٢ – أَخْبَرَنَا أَبُو حَازِمٍ الْحَافِظُ أنبأ أَبُو أَحْمَدَ الْحَافِظُ ثنا أَبُو الْعَبَّاسِ أَحْمَدُ بْنُ عَبْدِ اللهِ بْنِ سَابُورَ الدَّقِيقِيُّ بِبَغْدَادَ ثنا أَبُو نُعَيْمٍ الْحَلَبِيُّ عُبَيْدُ بْنُ هِشَامٍ ثنا إِبْرَاهِيمُ بْنُ مُحَمَّدٍ الْمَدَنِيُّ عَنْ حُسَيْنِ بْنِ عَبْدِ اللهِ بْنِ صُمَيْرَةَ عَنْ أَبِيهِ عَنْ جَدِّهِ قَالَ

قَالَ عَلِيٌّ ؓ عَمْدُ الْمَجْنُونِ وَالصَّبِيِّ خَطَأٌ  

See similar narrations below:

Collected by Suyūṭī