Diogenes of Apollonia

Diogenes of Apollonia

Diogenes of Apollonia was alive between 450 BCE and 400 BCE, though the specific dates are unknown, and was one of the last pre-Socratic philosophers, if not the very last. Originally from either the Cretan city of Apollonia or the Milesian colony of Apollonia, Diogenes’s exact origins are unknown, though he eventually found his way to Athens before being driven out for accusations of being an atheist.

Diogenes is responsible for several written works, from many different medical entries to his famous On Nature, where he talks about his belief in substance monism as we know it today. Substance monists believe that all things are truly different forms of the same thing, like how ice is another form of water.

He found his foundational beliefs as a philosopher in the ideas of Anaximenes of Miletus, the atomist who claimed that all things were air. Diogenes, too, claimed that all things are forms of air because only things that are alike can affect one another, and because of observations he knew that things do in fact interact. According to him, air is the breath of life that allows all things to occur, the basic element for everything. He also believed that air was intelligent, and that the soul was air.

While this may seem crazy today, Diogenes was not actually very far off from the truth. Hydrogen atoms, rather than the air, make up nearly all normal matter in the universe, and all other atoms form from the fusion of hydrogen in the cores of stars. Though the universe is also composed of dark matter and different forms of energy, all matter that humankind has interacted with thus far has evolved from one thing, the hydrogen atom. Hydrogen, like Diogenes’s idea of air, is essential to all life.

He focused on the physics of the world, rather than the ethics of humanity. For the centuries following Diogenes, physical philosophy fell to the shadow of the Socratic age of philosophy, meaning that the closest modern-day comparison to Diogenes would not actually be a common-era philosopher, but instead something of a theoretical physicist. Diogenes focused on the scientific areas of matter (as we now call it) and the universe, similar to scientists like Stephen Hawking and Albert Einstein. Although Diogenes later went on to teaching rhetoric and Greek politics, his truest lasting impact is on the within the sciences.

In addition to his theories on air, Diogenes of Apollonia also contributed to the medical industry with his work on vascular anatomy. Diogenes composed a relatively accurate layout of blood vessels in humans. He thought that some vessels were filled with air, the substance he found so fundamental to everything, and that others were filled with blood, and that death was found only when all air left the body. Though this was eventually proven untrue, his ideas of the structure and function of the human vascular system was crucial to later scientists who furthered his ideas and ultimately revolutionized the medical field.

Diogenes of Apollonia was the last of a long line of pre-Socratic philosophers and further popularized substance monism. A physicist at heart, he did not ask what is good? or what is bad? but merely what is? He found his answer in air, and although we now know this is wrong, he was on the right track to our current, modern understanding of our universe.

Quiz

1.    Why was Diogenes driven out of Athens?

2.    What was Diogenes of Apollonia’s most famous writing?

3.    What did Diogenes believe to be the substance that composed everything, including life and intelligence?

4.    To which medical field did Diogenes contribute?

Discussion

1.    Do you think that Diogenes was completely wrong in his position on substance monism, or do you think there is some truth to what he believed?

2.    Do you find the pre-Socratic philosophers, such as Diogenes of Apollonia, or the Socratic philosophers to be more fun to learn about?