The Dynamic Conception of Being in the First Philosophers and the Notion of φύσις

According to Aristotle, the "object" of study of the first philosophers was the φύσις. Even though the term appears for the first time in Heraclitus, the early answers to the question "what is the 'being' of τὰ ὄντα" present already it as a source of active and dynamic life, according to the etymology of φύσις. This is the meaning in Homer (Od. X.303), and this is also the case of water (Thales), air (Anaximenes), and the γόνιμα contained in the φύσις ἄπειρον (Anaximander, apud Ps.-Plutarch). The φύσις of Heraclitus inherits this meaning, because, for him, reality, "changing, is at rest" (fr. 84a).