Among them is the following: many people, on seeing a liar and hearing him speak, detect his falsehood—at times through immediate, self-evident knowledge, at times by inferential reasoning, and at times by a strong surmise. In the same way, when they behold a truthful prophet and listen to his words, his veracity becomes evident to them, whether by self-evident or reflective knowledge. Their first impression may begin as a powerful conjecture, then that conjecture grows stronger until it turns into certainty, just as happens with knowledge acquired from recurrent mass reports and repeated experiments: the first report yields a measure of probability, then it is reinforced by the second and third until it reaches certainty.

Many people have followed this route. Among those who pointed it out was Qadi Iyad, who said:

"If the fair-minded observer reflects on what we have already presented—his noble legacy, praiseworthy conduct, brilliance of knowledge, soundness of intellect, forbearance, overall perfection, all of his qualities, the testimony of his state, and the correctness of his speech—he will not doubt the soundness of his prophethood and the truth of his claim. This alone has sufficed more than one person to embrace Islam and believe in him. We have transmitted, on the authority of al-Tirmidhi, Ibn Qaniʿ, and others, through their chains, that ʿAbd Allah ibn Salam said: ‘When the Messenger of Allah, peace and blessings be upon him, arrived in Medina, I went to look at him; and when I had examined his face…’"