And even if there is a mistake in it the error is limited...

And even if there is a mistake in it the error is limited while if a non-learned person tries to act on his own he will do most of things in a wrong way. For example when a sick person goes to a doctor he usually takes a prescription and it is possible that the doctor might commit an error in it. However, his error will not have very serious repercussions in the prescription. (Here doctor denotes a knowledge and learned person).

However, if man stops following the advice of doctors and whenever he is sick he takes whichever medicine he likes, then indeed he would be performing a risky thing. He has put his life into danger. The result of this discussion is that the layman following a specialist is logical and reasonable proposition. This is also established that this type of following and seeking benefits is not a sign of helplessness of man, it is rather a proof of his capability.

Because we know that the sphere of knowledge is so vast that every field has hundreds of specialized branches and even if a person has the age of Nuh (a.s.) and the brain of Avicenna he cannot even specialize in 1/100 of the sciences. Thus there is no other option but that he follows the specialists in the fields in which he himself is not an expert.

For example if an engineer falls sick, he goes to a doctor and when a doctor wants to construct a house he goes to his favorite architect so that he may construct a plan for him. And when these two have some problem with their cars they go to an automobile mechanic. Also, those who are not specialists in Islamic law they follow the Mujtahids. Now the point remains that when people refer to the religious scholars and one dispensed appropriate advice why are they not allowed to ask questions?

It is like saying that: What is the problem in the patient asking for explanation and justification of all the medicines that the doctor has prescribed for him. Is it possible for the doctor to explain all the prescriptions to his patients? Even if we presume that the doctor agrees to do so, but what use would it be for a person who is neither an expert in biology nor pharmacology and how would he accept all this to be true?

Those who utter such things are indeed ignorant of the vastness of Islamic sciences. They dont know that to understand the Holy Quran and hundreds of thousands of traditional writings is not a job of a layman.