In this way the term potential and actual appeared in philosophy...

In this way the term potential and actual appeared in philosophy, and change came to be interpreted as emergence from potentiality to actuality. If this occurs instantaneously without a temporal gap it is called ‘generation and corruption.’ If it occurs gradually and with temporal gaps, it is called motion.

An Explanation of the Concepts of the Potential and the Actual The word potential ( quwwah ), whose literal meaning is power and ability, has various technical meanings in the sciences, and in philosophy it is used in several senses. The first is the potentiality of an agent who is the source of the production of an action. It seems that this is the first sense which was noticed by philosophers and whose relation to ‘action’ is clear.

It was then imagined that just as prior to performing a deed the agent has the ability to accomplish it, matter must also possess ability, readiness for acceptance and passivity in advance. In this way a second meaning appeared for potential. This can be called passive potential ( quwwah infi‘ālī ), and in this discussion it is this sense which is intended.

The third meaning of potential is resistance to an external factor, such as the resistance of the body to disease, and the opposite of this is called lack of potential ( lā quwwah ), and these are two kinds of dispositional qualities. It should be noted that the use of ‘potential’ by philosophers is more general than disposition ( isti‘dād ), for the term potential is also applicable to substance, contrary to disposition which is a kind of accident.

However, it was previously mentioned that substantial potential (prime matter) is not provable, and disposition is also an abstract concept, not an essential concept. Likewise, the concept of passive potential is abstracted by the comparison of two existents, prior and posterior, since the prior existent lacks the posterior existent and it is possible for the prior to possess the later.

Therefore, at the very least a part of the prior existent must remain and have a kind of composition and union with the posterior existent. Contrary to this, the expression ‘actuality’ is used as a result of abstraction from occurrence of the posterior existent. Hence, potentiality and actuality are two abstracted concepts neither of which is to be considered an essential concept.