In the narration which Abu Yahya al-Saji (may Allah have mercy on him) reported with his chain from Sayyiduna Mu'adh bin Jabal (may Allah be pleased with him) as marfu' (attributed to the Prophet): "And for (destroying) the intellect there are one hundred camels (as diyah)."
We have already mentioned our own chain for it, and a report has reached us from Sayyiduna Umar bin al-Khattab (may Allah be pleased with him) indicating that he ruled the full diyah for (destroying) the intellect.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الديات / Q16228
Abu al-Muhallab (may Allah have mercy on him) said that a man struck another on the head with a stone, and he lost his hearing, his speech, his intellect and his virility, so Sayyiduna Umar (may Allah be pleased with him) ruled four diyahs for him.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الديات / 16228
Al-Hasan al-Basri (may Allah have mercy on him) said concerning a man who was struck and lost his hearing, his sight and his speech because of the blow: there are three diyahs for him.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الديات / 16229
Sayyiduna Zayd bin Thabit (may Allah be pleased with him) said concerning a man who is struck and loses his intellect because of the blow: there is the full diyah for it.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الديات / 16230
Zayd bin Aslam (may Allah have mercy on him) said: The Sunnah has been established that for (taking) a person's life there is the diyah, and for the intellect, when it is lost, there is also the diyah.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الديات / 16231
Al-Hasan al-Basri (may Allah have mercy on him) was asked about a man who frightens another so much that he loses his intellect altogether. He said: If Sayyiduna Umar (may Allah be pleased with him) had come across such a person, he would certainly have taken the diyah from him.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الديات / 16232