Among Muslim scholars, attempts to classify the sciences began as early as the third/ninth century with al-Kindi, and multiplied thereafter. At first based on the Aristotelian division of the sciences into theoretical, practical, and productive, as described in Porphyry's Isagoge, these systems of classification became progressively more elaborate. Islamic disciplines were added to the ancient sciences, and religious and metaphysical knowledge in the sense of gnosis came to occupy the highest levels.

One of the earliest and most influential classifications was that of al-Farabi, contained in his Enumeration of the Sciences (Ihsa’ al-'ulum) known in the West as De Scientiis, from the Latin translation by Gerard of Cremona, as well as in a Hebrew translation. Although partly eclipsed by his successor Avicenna, al-Farabi (d. 850) left his imprint upon most of the Muslim thinkers who followed him, as can be seen from the fact that his classification of the sciences was adopted, with only minor changes, by Avicenna (d. 1037), al-Ghazali (d. 1111), and Averroes. Curiously enough, although al-Farabi himself wrote treatises on alchemy, the interpretation of dreams, and other esoteric sciences, he did not include them in his classification. In this respect, he was followed by the more rationalistic philosophers of the later centuries.

His classification, according to the Enumeration of the Sciences, may be summarized as follows:

I. Science of language: syntax, grammar, pronunciation and speech, poetry

II. Logic [corresponding to the Categories and On Interpretation of Aristotle.] Additional parts of logic:

1. Premises of the syllogism [corresponding to the Posterior Analytics of Aristotle]

2. Syllogisms and dialectical proofs [corresponding to the Topics of Aristotle]

3. Errors in reasoning [corresponding to the On Sophistical Refutations of Aristotle]

4. Oratory [corresponding to Aristotle's Rhetoric]

5. poetry [corresponding to Aristotle's Poetics]

III. The preliminary sciences:

1. Arithmetic: practical and theoretical

2. Geometry: practical and theoretical

3. Optics

4. Science of the heavens: Astrology; Astronomy

5. Music: practical and theoretical

6. Science of weights

7. Science of tool-making

IV. Physics (sciences of nature) and Metaphysics (science concerned with the Divine and the principles of things)

Physics [corresponding to the Physics of Aristotle]:

1. Knowledge of the principles which underlie natural bodies

2. Knowledge of the nature and character of the elements, and of the principle by which they combine to form bodies

3. Science of the generation and corruption of bodies

4. Science of the reactions which the elements undergo in order to form compounds

5. Science of compound bodies formed of the four elements and their properties

6. Science of minerals

7. Science of plants

8. Science of animals

Metaphysics [corresponding to the Metaphysics of Aristotle]:

1. Knowledge of the essence of beings

2. Knowledge of the principles of the particular and observational sciences (the "first philosophy" of Aristotle)

3. Knowledge of noncorporeal beings, their qualities and characteristics, leading finally to the knowledge of the Truth, that is, of God, one of whose names is the Truth.

V. Sciences of Society

1. Jurisprudence (law or fiqh) [corresponding to the Ethics of Aristotle]

2. Theology (dialectics or kalam,i.e., the persuasive discourse on religion) [corresponding to the Politics of Aristotle]


(based on S. H. Nasr, Science and Civilization in Islam, pp. 60-62, with some revision)