Gibbon acknowledged Muhammad’s character was too elusive to fix

Evidence

Had I been intimately conversant with the son of Abdallah, the task would still be difficult and the success uncertain … could I truly delineate the portrait of an hour, the fleeting resemblance would not equally apply to the solitary of Mount Hera, to the preacher of Mecca, and to the conqueror of Arabia. — Norman Daniel, Islam and the West, 1628