Potentiality and Actuality - The Importance of Actuality in Aristotle's Philosophy

The Importance of Actuality in Aristotle's Philosophy

The actuality-potentiality distinction in Aristotle is a key element linked to everything in his physics and metaphysics.

Aristotle describes potentiality and actuality, or potency and action, as one of several distinctions between things that exist or do not exist. In a sense, a thing that exists potentially does not exist, but the potential does exist. And this type of distinction is expressed for several different types of being within Aristotle's categories of being. For example, from Aristotle's Metaphysics, 1017a:

• We speak of something being "seeing" whether it is currently seeing or just able to see.
• We speak of someone having understanding, whether they are using that understanding or not.
• We speak of corn existing in a field even when it is not yet ripe.
• People sometimes speak of a figure being already present in a rock which could be sculpted to represent that figure.

Within the works of Aristotle the terms energeia and entelecheia, often translated as actuality, differ from what is merely actual because they specifically presuppose that all things have a proper kind of activity or work which, if achieved, would be their proper end. Greek for end in this sense is telos, a component word in entelecheia (a work that is the proper end of a thing) and also teleology. This is an aspect of Aristotle's theory of four causes and specifically of formal cause (eidos, which Aristotle says is energeia) and final cause (telos).

In essence this means that Aristotle did not see things as matter in motion only, but also proposed that all things have their own aims or ends. In other words, for Aristotle (unlike modern science) there is a distinction between things with a natural cause in the strongest sense, and things that truly happen by accident. He even says that for any possibility (dunamis) to be become real and not just possible, requires reason, and desire or deliberate choice. Because of this style of reasoning, Aristotle is often referred to as having a teleology, and sometimes as having a theory of forms.

While actuality is linked by Aristotle to his concept of a formal cause, potentiality (or potency) on the other hand, is linked by Aristotle to his concepts of substance and material cause. Aristotle wrote for example that "matter exists potentially, because it may attain to the form; but when it exists actually, it is then in the form".