There are secrets and hidden wisdom in the Islamic laws even though we may not be able to discover them. Generally speaking, no law has been enacted without a reason or logic. God, the Wise and All-Knowing, does not command humankind to do an act unless there is a reason or wisdom in it. Therefore, we must abide by every rule or command that has been obtained through the Quran, authentic traditions, reason and decisive knowledge, though we may not know the reason behind it.
Apart from this, it can be said that one of the reasons behind the legislation of Islamic laws is to create a form of economic balance, to eliminate class gap and to provide psychological and spiritual peace and tranquility to the family and society especially the low-income groups.
There are secrets and hidden wisdom in the Islamic laws even though we may not be able to discover them. Generally speaking, no law has been enacted without a reason or logic. The Islamic laws and injunctions are subservient to real causes; they are rooted in physical, spiritual, economic and social realities. Basically, the value of a man's deeds depends squarely on the degree of his knowledge, insight and faith. This requires him to conduct a research about the philosophies and rationales of Islamic rules and laws to know what those laws have been created for and where do they lead him to.
When it comes to knowing the secrets and philosophies of Islamic laws, we should not consider the discoveries made by the modern science as sufficient nor should we pass any judgments about divine rules and injunctions on the basis of those scientific achievements. That is because, firstly, the divine laws have been based on man's psychological and physical aspects. Secondly, we must admit that our knowledge of the surrounding world and of complex psychological and spiritual realities is very little.
The Holy Prophet of Islam has been reported as having said, "O people, you are like a patient and the Lord of the Worlds is like a doctor [Who prescribes the healing medicine]."
Obviously, an ailing person who believes in the scientific and technical competence of a doctor, will use every medicine which the doctor prescribes even if he does not know what the biological effects of the colorful medicines are and how they will affect his health. However, since he believes in the doctor's prescription, he acts according to it.
In short, the discussions about the hidden logic behind the laws and the right to discuss about them is one thing and to obey these laws is another. The latter is not conditional to former.
We discuss about religious laws to increase our knowledge about their benefits, importance and different effects. We do not discuss these things to decide whether we should practice these laws or not.
It is like asking the doctor about our treatment, about the medicines prescribed; their effects and benefits etc. so that we can acquire more information about these things. However our taking of medicine is not in any way based on his explanation, otherwise it would be necessary that the person should also be a doctor. In fact, knowing the effects of the medicines is good but it is not a necessary condition for taking the medicine. Hence one should take the medicine even if he does not know the reason. The position is the same with divine laws; man's knowledge is limited and he cannot have access to the philosophy of every rule and injunction.
Therefore, we must abide by every rule or command that has been obtained through the Quran, authentic traditions, reason and decisive knowledge, even though we may not be able to discover its reason and consequences.
Of course, it can be said that one of the reasons behind the prohibition of using gold and silver is to create a form of economic balance and to eliminate class gap and it will help the poor not to feel humiliation. It will cause society to be psychologically, socially and economically at peace and tranquility. It has been stated in a tradition that: "Gold and silver dishes are used by those people who do not believe in God." 
 - "ایها الناس انتم کالمرضی و ربّ العالمین کالطبیب" Tabarsi, Ahmad bin Ali, Al-Ihtijaj, Beirut, Dar al-Nu'man, vol.1, pg. 45; Mirza Hussein Noori, Mustadrak al-Wasail, Qom, Aalulbayt, 2nd edition, 1408, vol.3, pg. 177.
 - See: The Philosophy of Ijtehad and Taqlid by Muhammad Dashti, Qom, Amirul Momeneen Research Institute, 1st edition, pg. 163; Mutahhari, Murteza, Islam and Requirements of Time, Tehran, Sadra Publications, 16th edition, pg. 20; Hadavi Tehrani, Mahdi, Beliefs and Questions, Qom, Khanae Kherad, 2nd edition, pg. 51 – 55.
 - Kulayni, Al-Kafi,vol.2, pg. 268, hadith 7, Dar al-Kutub al-Islamiyah, Tehran 1365 (Islamic solar calendar).
"عِدَّةٌ مِنْ أَصْحَابِنَا عَنْ سَهْلِ بْنِ زِیَادٍ عَنْ عَلِیِّ بْنِ حَسَّانَ عَنْ مُوسَى بْنِ بَکْرٍ عَنْ أَبِی الْحَسَنِ مُوسَى ع قَالَ آنِیَةُ الذَّهَبِ وَ الْفِضَّةِ مَتَاعُ الَّذِینَ لَا یُوقِنُونَ".
 - See index: The philosophy of prohibition of Gold for man, question 759 (site: 799).