Medicine considers the human body as to the means by which it is cured and by which it is driven away from health.
That whose existence is necessary must necessarily be one essence.
Therefore in medicine we ought to know the causes of sickness and health.
Wherefore the rational soul shall surely depart (migrate, travel) taking along the kernels of the other powers after death ensues.
As to the mental essence, we find it in infants devoid of every mental form.
If the notion of necessary existence is divided into a multitude, it must be divided in one of the following two ways: either it is divided according to the manner of its division by differentiae or according to the manner of its division by accident.
It is evident that everything which does not exist at first and then exists, is determined by something other than itself.
The knowledge of anything, since all things have causes, is not acquired or complete unless it is known by its causes.
The world is divided into men who have wit and no religion and men who have religion and no wit.
Now it is established in the sciences that no knowledge is acquired save through the study of its causes and beginnings, if it has had causes and beginnings; nor completed except by knowledge of its accidents and accompanying essentials.