hadith
6864
۞
Imam Ali (AS) said, Indeed, the one who is asked about that which he does not know should never consider it demeaning to say “I dont know”.
الإمامُ عليٌّ (عَلَيهِ الّسَلامُ) : ألا لايَسْتَقْبِحَنَّ مَنْ سُئِلَ عَمّا لايَعْلَمُ أنْ يَقُولَ لا أعْلَمُ