Nahj al-Balāgha
Hadith 1667٣٨. وَقَالَ (عليه السلام) لِابْنِهِ الْحَسَنِ (عليه السلام): يَا بُنَيَّ، احْفَظْ عَنِّي أَرْبَعاً وَأَرْبَعاً، لَا يَضُرَّكَ مَا عَمِلْتَ مَعَهُنَّ: إِنَّ أَغْنَى الْغِنَىُ الْعَقْلُ، وَأَكْبَرَ الْفَقْرِ الْحُمْقُ، وَأَوحَشَ الْوَحْشَةِ الْعُجْبُ وَأَكْرَمَ الْحَسَبَ حُسْنُ الْخُلُقِ.
38. Amīr al-mu’minīn, peace be upon him, said to his son al-Ḥasan: O my son, learn four things and (a further) four things from me. Nothing will harm you if you practise them. That the richest of riches is intelligence; the biggest destitution is foolishness; the wildest wildness is vanity and the best achievement is goodness of the moral character.