Non-existence as a Cause in Aristotle's Physics

One of the issues that occupied the minds of many thinkers in ancient times was the issue of change, generation and corruption, and the role of principles in these processes. The positions of some early philosophers led to contradictions such as the denial of motion and any stability in existents. Aristotle, however, considers nature to be subject to motion, and although he considers matter and form as the source and main cause of any creation and change, he also considers a third element called "non-existence" necessary for change and generation and corruption in nature. In this way, he solves the old puzzle above. As it is well known, matter and form are among Aristotle's four causes; but in spite of the explicit statements about non-existence, it is not considered as a cause, while the study of its role shows that it can also be considered as a kind of cause, because it provides the basis for the creation and change of objects. In this article, by examining the role of non-existence in nature, we try to show that without it, creation and change in existents is not possible and in fact it is a kind of cause.