Can an Illiterate Person Guide Humanity?

The Prophet Muhammad (saw) was an uneducated and illiterate person. In that case, is it possible for such a person to guide humanity by himself on many issues such as creation, the universe, the history of humanity, belief in Allah, the realm of ghaib, post-death, salvation of man, etc.? It should also be noted that the Islamic civilization, which has an important place in the history of civilization, was established with the values brought by the Qur'an. Again, these values have been the main source of the Muslim ummah on the path of goodness and virtue for more than fourteen centuries. Is it possible for an illiterate person to give such guidance to humanity without revelation? 

If we say the opposite, wouldn't we, in a sense, claim the following: An uneducated, illiterate person who grew up in a place far from civilization can guide and master all humanity in issues such as past-future, visible-unseen, life-afterlife, true-false, right-wrong.