Becoming as formulated by Aristotle
"The basic problem confronting Aristotle was that of explaining the relationship between form (essence) and matter (substance); it was necessary to find a principle or natural process impelling matter to take on some definite form, or, from the reverse point of view, enabling form to become actual in matter. The idea of a rose becomes real, is perfected, when it achieves actuality in the material substance, the rose itself; similarly matter or substance exists only when it takes on some form, some design. The natural world is dynamic, not static, for it is a beautiful active process wherein the material world takes on some form or design, and is thus constantly perfecting itself."
Sahakian, History of Philosophy (Barnes & Noble, 1968)