Since the devastation of Dorian in the Bahamas is in the news, and since most Epicurean blogs tend to focus on the ethics and ignore the physics, I thought I’d revisit some of what Epicurean philosophy has to say about hurricanes. Towards the end of a previous essay titled Lucretius Against the Creationists, I had included Lucretius’ detailed, accurate, and poetic account of how rain and clouds form in On the Nature of Things.
Today, I’d like to focus on how all things are relative to each other in Epicurean cosmology, and how science sheds light on the many nodes of interrelatedness. For instance, we know that the force of gravity works different at different heights, and so people weight a little less when they are at higher altitude–for instance, a man at sea level may weigh a little more than when he stands on top of a mountain.
According to this article on air pressure and how it affects the weather, “atmospheric or air pressure is the force per unit of area exerted on the Earth’s surface by the weight of the air above the surface“. Also–as you may have noticed if you’ve ever paid attention to your weatherman–a low pressure system,
also called a depression, is an area where the atmospheric pressure is lower than that of the area surrounding it. Lows are usually associated with high winds, warm air, and atmospheric lifting. Under these conditions, lows normally produce clouds, precipitation, and other turbulent weather, such as tropical storms and cyclones.
Let’s consider this in light of the elementary understanding that the first atomists established, as seen in Epicurus’ Letter to Herodotus. All things in nature are made up of particles and void. Particles exhibit properties according to the laws of nature: we know that particles can be classified by element (nitrogen, neon, hydrogen, etc.) according to how many protons and electrons they carry within them. When these particles combine, they create compounds which exhibit increasingly complex properties. We observe that the only property that the void exhibits is that it yields, so that its space can be filled by particles.
A low pressure weather system has less particles, less density; whereas a high pressure area has an overflow of particles and density. Therefore, it yields, absorbs, the water and other particles all around it and quickly becomes cloudy and rainy. This means that if there are clouds in one place, and a low pressure system settles north of it, then those clouds will naturally move north to where the low pressure is, and so measurements of low pressure allow climatologists to predict what the weather will be like in any one location. This is just one application of the fundamentals of physics that we find in the Letter to Herodotus: in terms of dynamics and motion, rather than atoms and void, we must think in terms of asserting and yielding movements between the particles, which are always in motion because they are surrounded by void (which, by its nature, yields).
Epicurus also predicted there that, since the laws of nature are the same everywhere and at all times, we would find in other worlds similar phenomena as what we find here on Earth–from worlds similar to and different from our own, to lifeforms similar to and different from our own. In our own solar system, we see similar weather patterns as those we see on Earth in the Saturnian moon of Titan. It has an atmosphere, weather systems, it rains, it has lakes and rivers … except that there–due to its distance from the sun–the lakes, rivers and rain contain methane instead of water, because methane becomes liquid at a much cooler temperature. Water only exists as hard ice in Titan.
There are many more phenomena (like the orbits of all the heavenly bodies) that are explained by these fundamentals related to yielding and asserting / atoms and void. During this hurricane season, stay safe, and take up the study of nature beginning from the very foundations–from Epicurus!