Group of Sciences in Islam and their Scope
By: Prof. Dr. Mahdi Gulshani
Besides, we think that the group of sciences belonging to the category of wajib kifa'i is much more larger than what Al‑Ghazzali would have us believe. Moreover, we think that the parsimony he shows regarding those sciences which may be included in this category, does not harmonize with the teachings of the Quran and the Prophet's sunnah.  Our reasons for not accepting such restrictions on learning are as follows:
1. In most of the Quranic verses and traditions, the concept of `ilm (knowledge) appears in its absolutely general sense, as can be seen from examples given below: Say: Are those who know and those who do not know alike? (39:9) (God) taught man what he knew not. (96:5)
And He taught Adam all the names; then showed them to the angels, saying: "Tell me the names of these, if you are right."(2:31)
Anyone who pursues a course of acquisition of knowledge, God will ease his eventual access to paradise. (prophetic tradition; source: Munyat al‑Murid, p . 12, Najaf A.H. 1370)
Similarly other Quranic verses and traditions confirm that knowledge does not mean only learning of the principles and laws of the Shari'ah. We may note some further examples: And certainly We gave knowledge to David and Solomon, and both (the apostles) said: `All praise is God's who made us to excel many of His believing servants. And Solomon succeeded David and he said: `O people! We have been taught the language of the birds, and we have been granted (plenty) of everything; surely, this is manifest grace (of God)'. (16:15)
We see that these two prophets consider the knowledge of the language of birds to be a Divine blessing.
Do you not see that God sends down water from the shy, then We bring forth with it fruits of various colours, and in the mountains are streaks, white and red and of various colours and others intensely black? And of men and beasts and cattle are of various colours likewise; only those of His servants endowed with knowledge fear God; surely, God is Almighty and Forgiving. (35:27 28)
Clearly, the word `ibadihi al‑`ulama' (His servants endowed with knowledge) occurring in the above verse refers to those who are aware of the laws and mysteries of nature and creation, and who acknowledge in all humility the greatness and majesty of God. The following traditions of the Prophet (S) also point in the direction of the most general sense of the word "knowledge".
Seek knowledge by even going to China. 
The most learned of men is one who collects bits of knowledge from others and thus enhances his own knowledge. 
Anyone who desires the good of present life should seek knowledge. Anyone who desires the life of Hereafter should seek knowledge. And anyone who wants to do well in this life and in the next world should seek knowledge. 
Accept whatever adds to your wisdom, irrespective of the nature of the source. 
From these sayings of the great Prophet of Islam and similar traditions which have been narrated from the Ahl al‑Bayt  (the spiritual successors of the Prophet) the truth emerges that such recommendations for acquisition of knowledge are not confined to the knowledge of the principles and laws of the Shari`ah; because, as is obvious, China was not a centre of theological studies in those days but was famous for its crafts and industry. Moreover, it is clear that the laws of Shari ah and Islamic doctrines cannot be learnt from polytheists and infidels.
2. Another reason for not considering "desirable" knowledge to be limited to the religious and theological studies is the precious heritage left by the Muslim scholars of the first several centuries of Islamic civilization and that has come down to our own time. As is also confirmed by modern historians, Muslim scholars were at the vanguard of the scientific tradition for centuries and their books were used as text‑books in Europe for several hundred years.
In fact the major reason why Muslim scholars rejected the intellectual traditions of other countries was that they did not see any separation between the goal of religion and the ends of knowledge and were convinced that both religion and knowledge were aimed at illuminating the unity of nature and as a result the oneness of the Creator. Accordingly, it was on the basis of this conviction of intrinsic fusion of religion and knowledge that religious coaching and rational training were considered as aspects of a single discipline in religious schools and mosques.
3. To set aside a group of sciences on the pretext that they do not have as much value as the religious studies is not correct. Because, whatever field of knowledge is conductive to preservation of the strength and vitality of an Islamic society, its knowledge is wajib kifa’i in the same fashion as scholarship in religious sciences has been pointed out as a wajib kifa'i for the Islamic society in the following verse of the Quran: It is not for the believers to go forth totally (to acquire scholarship in religion); but why should not a party of every section of them go forth, to become learned in religion, and to warn their people when they return to them, that haply they may beware? (9:122)
So we have discovered that the word 'Urn as it occurs in the Book and sunnah appears in its more general sense than what may apply exclusively to the religious studies. Nevertheless, it may be said that Islam has only dissuaded Muslims from preoccupying themselves with. any pursuit of such branches of knowledge whose harm is greater than their benefit (like magic and sorcery and games of chance used for gambling). The relevant sayings of the Prophet (S) may be noted: We seek God's refuge from knowledge that does not benefit. 
O God! Benefit me through knowledge that You have bestowed on me, teach me whatever would benefit me, and increase me in knowledge. 
Ali (A) is related as having said: There is no good in knowledge which does not benefit. 
Knowledge is too immense in scope for anyone to be able to contain it. So learn from each science its useful parts. 
. Al‑Ghazzali, Ihya ulum al‑din, vol. I, p. 39.
. Ibid, vol. I, p. 14. Also see Muhajjat al‑bayda', vol. 1, p. 21, and Bihar al anwar, vol. I, p. 57.
. Shaykh Saduq, Amali, p. 19. Also see Safinat al‑bihar, vol. 2, p. 219.
. Al‑Nizam al‑tarbawi fi al‑Islam, p. 188.
. Mukhtar al‑ahadith al‑nabawiyyah wa al‑hikam al‑Muhammadiyyah, p. 70.
. Nahj al‑balaghah. Dublished by Dr. Subhi al‑Salih, p. 481.
.Ibn Majah, Sunan, No. 250; also see Misbah al‑shariah, chapter 60.
. Al‑Tirmidhi, Sunan, the chapter on da'wat, Ibn Majah, Sunan, `introduction'.
. Nahj al‑balaghah, published by Dr. Subhi al‑Salih, p. 393.
. `Abd al‑Wahid Amadi, Ghurar al‑hikam wa durar al‑kalim, p. 42.