Chapter 1

The empiricists say that medicine is derived from experience, experience being the knowledge which is obtained through the senses. They also say that the principles and rules of medicine result from four things: incident (ittifaq), intention (iradah), comparison (tashbih), and the use of something in one case that was used in another similar case (naql min shay' iki shabihihi).

`Incident' is in turn divided into two parts: natural incident, such as a nosebleed, a sweat, vomiting, or something similar which occurs naturally and which brings either benefit or harm; and `accidental' incident, which occurs in a human being neither naturally nor through his intention, and which similarly results in either some benefit or some harm. An example of an accidental incident is when a sick person falls and blood flows out of him.

`Intention' means when something is experienced by choice; the motive for such an `experience' may be something seen in a dream or other similar thins.

`Comparison' is when the physician employs one of the three instances mentioned above (that is intention, natural incident, or accidental incident) when a new case presents itself. For example, when he sees that his patient, who has a bloody fever, obtains relief through a flow of blood from his nose, whether that occurs naturally, acciden­tally, or through his personal will, then he will try drawing blood in similar illnesses.

Finally, naql is the method employed when the physician en­counters an illness which he has not seen before, or which he has seen but for which there is no proven treatment. In this case he will resort to naql, that is he will use a medicine which has been proven in the case of one illness in a similar illness, or will use a medicine proven in the case of one organ of the body for another similar organ; or if he does not have access to the proper medicine, he will use a similar one.