Compendium on the Soul

just as an accident In philosophy, an "accident" is a property that exists in something else, like color in an apple, rather than existing on its own. arises from its subject. From accidents, however, one arrives at the knowledge of the substance: for this reason, Avicenna proves in this chapter that these powers of the soul exist in reality, so that through the knowledge of these powers, our intellect may conclude by necessity that the substance of the soul itself is real. I, Andreas Bellunensis Andrew of Belluno, a 15th-century physician and translator known for his work on Avicenna., have said these things to stimulate sharper minds and those who have greater skill in the speculative sciences; and under the same protestation, I shall note down in this notebook the following things which I have gathered from the Arabic commentators.

However, there is a doubt concerning Avicenna's words, because no science proves that its own subject exists, since the subject is presupposed to exist. For this reason, Aristotle in his book On the Soul does not prove that the soul exists, but presupposes its existence as the principal subject in the science of the book On the Soul, and so forth. The answer is that no science proves its subject exists a priori original: "à priori"; reasoning from causes to effects., but a posteriori original: "à posteriori"; reasoning from observed effects back to the cause. and through effects, the subject of a science can be demonstrated—especially to someone opposing or doubting, and seeking demonstration and certainty as to whether the subject of the science exists in reality or not.

And in this way, Avicenna, in the sixth book of his Natural Philosophy and in this first chapter of this compendium, has demonstrated through effects and a posteriori that the soul—which is the subject of this science—is something real, and not something imaginable and false, as many foolish people think who do not perceive or assert anything real in nature except that which is perceived by the senses. This is also written by Avicenna in the book of Aphorisms on the Soul, in the ninth aphorism, where he speaks thus: "Man, because he is accustomed to apprehending or knowing things with the senses, becomes by this a believer that whatever is not known through the senses has no existence," etc.

Reason is not entirely hindered, that is, reason does not doubt entirely.

Therefore, in this first chapter, Avicenna demonstrates a posteriori to one who is opposing, or doubting and inquiring, that the individuals of this name "soul," which is the subject in this science, are really in nature.

THEN we find that they [bodies] differ after that in the fact that they are moved A (supply: by diverse motions), because some are moved by circular motion, such as the celestial bodies, and some by straight motion. AND IF not, then there would not be found that which B possesses rest, etc. That is, if it were not true that all bodies, which share in the fact that they are "body," differ in the fact that they are moved by the diverse motions mentioned above: then it would follow that there would not be found anything possessing rest, indeed there would not be found, etc. This consequence is proved: because either all bodies differ through the aforementioned diverse motions, or they do not differ. If it is said that they do not differ by diverse motions, then it must be asked: do all bodies agree in motion, so that they are moved by a similar, non-diverse motion? Or do all bodies agree in rest, so that all bodies are at rest? And it is clear that it should not be said that they are at rest, because the celestial bodies are moved by necessity with a continuous circular motion. If, however, it is said that all bodies do not differ by motion, but agree in motion: it follows that all bodies agree in circular motion, which...