[LECTURE 5: REVIVALS OF NATURAL PHILOSOPHY]

THE REVIVALS OF THE NATURAL PHILOSOPHY

Empedocles of Akragas (443-444 B.C.)
Anaxagoras of Klazomené (500-424 B.C)
The Atomists
‹Leucippus of Abdera, Elea (430 B.C.) & Democritus of Abdera (420 B.C.)‹

As you can easily see from the above discussions of the Italian philosophy, early Greek Natural philosophies, particularly like those of Miletian philosophies and even the Pythagoreans (not Pythagoras himself apparently), were greatly challenged by the Eleatic philosophy and had to abandon one of the most fundamental principles in understanding the universe, and develop a possible alternative way of understanding it.

How were they challenged? Parmenides' philosophy emphatically asserted that Non-being does not (exist), and it clearly showed that change be utterly impossible in Reality. As long as we accept the Parmenidean apodeictic principles: Being exists, while Non-being does not (exist), any ontological doctrine which purports that Being is one and many at the same time, and they change into one another is logically untenable but also really unthinkable. The Eleatic philosophy threatened the foundation of the Ionian natural philosophy, because the reality the Ionian philosophy talked about must be explained by the principle of the changes, i.e., condensation and rarefication. In other words, the basic approach of Ionian natural philosophies was to establish one principle of nature (e.g. water, air ) and explain multitude of phenomena of reality by means of this principle's change (either condensation or rarefication).

As long as the genuine reality consists in either one or more than one principle of matter, the new natural philosophers had to accept the Eleatic challenge such that one matter does not change into another and that there cannot exist two Beings, as it implies the existence of Non-being.

Thus, they accepted in a sense and tried to meet the challenge of the Eleatic School and they, too, took change as unacceptable. Namely, they refused to comprehend the change in the sense of the metamorphosis of one material thing into another, or its condensation or rarefication. Thus, they who were challenged by the Eleatic School attempted to explain the phenomena of multiplicity and those of change in nature by means of mixture and separation, while they held that the basic natural elements were unchanging.

In stead, for example, Empedocles held that the ultimate reality are the four roots (stoicheiai) of nature, namely earth, water, air and fire, which never change into one another: Anaxagoras held that everything is in everything, while the atomists held that nature consists of an infinite number of the ultimately indivisible entities (atoma) which cannot be known by our senses. The change and variety of nature is now explained by the principle of mixture and separation.
Because of this, those natural philosophers were forced to make a distinction between the world of sense experience and the world of reason and held the latter to be the true reality. The opposition between senses and reason as the epistemological faculties was sharpened and in the cognition of nature, the antagonism between nomos and physis became more eminent.

Empedocles of Ekragas (445/4 B.C.)

Empedocles' Life and Accomplishments

Empedocles was born in Ekragas (today's Agrigentum in Sicily). We possesses a record, which states that Empedocles visited Thurioi, that was built by the great Athenian Admiral an