The only way he would know what his like and dislikes is...

The only way he would know what his like and dislikes is revelation or a messenger. On e does not receive revelation he must find the messengers and when finds the messengers he will know that they the Divine authority and that obedience to them is necessary.

I say to people, "Do you know that the messenger of Allah was the Divine authority over His creatures?" They say, "Yes, he was the Divine authority." I then ask, "After the messenger of Allah who was the Divine authority over His creatures?" They said, "After the messenger of Allah the Divine authority is the Holy Quran." I considered the Holy Quran and found out that various kinds of people consider this Holy Book as support for their beliefs.

For example the Murji'a (people who say Allah has postponed punishment), the pre-determinists and the atheist who even do not believe in it but take it as the basis for their arguments against the others. I then learned that the Holy Quran can not serve as Divine authority without a guardian whose words from the Holy Quran would be the truth.

I then ask the people, "Who is the guardian of the Holy Quran?" They say, "Ibn Mas'ud knew the Holy Quran, 'Umar knew it and Hudhayfa knew the Holy Quran." I ask them, "Did they know all of the Holy Quran?" The people say, "No, they did not know all of it." I have not found anyone who would know all of the Holy Quran except Ali ibn abu Talib (a.s.).

It is a fact that if any issue would emerge that needed a Quranic solution, except for Imam Ali (a.s.) every one of the others would, in many cases, say, "I do not know." Only Imam Ali (a.s.) would say, "I know." I then acknowledge that Imam Ali (a.s.) is the guardian of the Holy Quran and obedience to him is obligatory and he is the Divine authority over the people after the Holy Prophet (s.a.).

Whatever Imam Ali (a.s.) has said from the Holy Quran is the truth." The Imam (a.s.) said, "May Allah grant you blessing." H 414, Ch. 1, h 3 Ali ibn Ibrahim has narrated from his father from al-Hassan ibn Ibrahim from Yunus ibn Ya'qub who has said the following. "In the presence of Imam abu 'Abdallah (a.s.) once there was a group of his followers consisting of Humran ibn 'Ayun, Muhammad ibn al-Ni'man, Hisham ibn Salim, al-Tayyar and others among whom was also Hisham ibn al-Hakam, a young man.