Al-Kāfi
Hadith 4752- عِدَّةٌ مِنْ أَصْحَابِنَا عَنْ أَحْمَدَ بْنِ مُحَمَّدٍ عَنِ ابْنِ فَضَّالٍ عَنِ ابْنِ بُكَيْرٍ عَمَّنْ حَدَّثَهُ عَنْ أَبِي عَبْدِ اللهِ (عَلَيْهِ السَّلام) قَالَ التِّجَارَةُ تَزِيدُ فِي الْعَقْلِ.
2. A number of our people have narrated from Ahmad ibn Muhammad from ibn Faddal from ibn Bukayr from those who narrated to him who has said the following: “Abu ‘Abd Allah (a.s.), has said, ‘Doing business increases one’s power of reason.’”