What is the prescribed compensation for the loss or impairment of intellect ('aql)?

Primary text

The full blood money (*diyah*) is due for the loss of intellect ('aql). This is because intellect is the greatest faculty in terms of value and the most significant of the senses in terms of benefit; it distinguishes humans from animals, enables comprehension of truths, guides toward benefit, allows avoidance of harm, and is essential for religious obligation, holding authority, sound transactions, and performance of worship, thus meriting the full *diyah* more than other senses. If the reduction in intellect is measurable, such as alternating between sanity and insanity daily, the compensation is proportional to that known measure, analogous to the compensation for partial loss of fingers. The Prophet's letter to 'Amr ibn Hazm stipulated that *diyah* is due for the 'aql.