Since the principles of all causes are not the same...

Since the principles of all causes are not the same, it is necessary to mention the types of cause and the terminology appropriate to them before discussing the laws of causality and the principles of cause and effect, so that when we turn to related problems mistakes are not made.

Cause in its general sense, that is, an existent upon which another existent is somehow dependent, may be classified in various ways, of which the following are the most important: Complete and Incomplete Causes: A cause may either be such that it is sufficient for the realization of the effect, or such that it is not sufficient for the realization of the effect even though that effect cannot be realized without it. The former sort of cause…