It's time to refresh Stoicism for the 21st century and beyond, don’t you agree? This philosophy has been in existence since the 4th century BCE, and a lot has evolved since then. Recently, I initiated the School for a New Stoicism, aimed at adapting this timeless and practical philosophy to contemporary life.

I am certainly not the first to propose modernizing Stoicism. Larry Becker's notable work, A New Stoicism, stands out as a serious attempt in this direction. I contributed to this dialogue with my version of Epictetus’s Enchiridion, titled A Field Guide to a Happy Life.

My efforts differ from those of writers like Don Robertson and John Sellars, who focus on popularizing Stoicism. Occasionally, these goals intersect, as seen in Robertson’s Stoicism and the Art of Happiness or Bill Irvine’s A Guide to the Good Life.

In this series of essays, I intend to achieve three objectives: first, to present a straightforward summary of the core concepts that define Stoicism—clarity on our foundation is crucial for understanding our direction. Second, to analyze three significant modern attempts to adapt Stoicism. Finally, I will outline my vision for what a contemporary interpretation of Stoicism could resemble.

This essay will delve into ancient Stoic physics; subsequent pieces will address ancient Stoic logic and ethics. Following that, I will explore Becker’s New Stoicism (the fourth essay), Piotr Stankiewicz’s reformed Stoicism (the fifth), and Steven Gambardella’s interpretation (the sixth). The series will conclude with my own proposals. How does that sound?

My examination of ancient Stoic physics, logic, and ethics reflects my understanding of these topics developed over the past decade. For those seeking a deeper scholarly exploration, I recommend the article by Marion Durand and Simon Shogry in the Stanford Encyclopedia of Philosophy, especially its bibliography.

Founded by Zeno of Citium around 300 BCE in Athens, Stoicism consists of three main components: physics, logic, and ethics. "Physics" derives from the Greek term phusis, which means nature, and involves the study of the natural world, encompassing what we now term science and metaphysics. "Logic" covers not just formal reasoning but also epistemology, language philosophy, and philosophy of mind. "Ethics" encompasses discussions beyond mere right and wrong, including human character and social behavior.

The Stoics posited that living well (ethics) hinges on understanding our world (physics) and reasoning accurately about it (logic)—a notion that seems quite rational!

I begin with physics because Durand and Shogry do, but we could just as easily have started with logic. Ethics must come last, as it relies on both physics and logic.

It is essential to remember that the goal of the first three essays is to present a comprehensive view of ancient Stoicism, not to modernize it just yet. While I will occasionally draw comparisons to modern science, logic, and ethics, these will solely serve to clarify ancient Stoic thought.

Stoic Ontology: Understanding Reality

The Stoics distinguished between what is real and what exists, which may seem perplexing today. They argued that only corporeal entities—those made of substance—truly exist. Therefore, you, I, and every physical object in the universe are corporeal and thus exist. Essentially, being encompasses all that can causally interact with other entities. Causality is the hallmark of existence: if something exists, it has causal influence; if it has causal influence, it exists (and is corporeal).

A significant implication of this perspective is that the soul must also be corporeal, as it possesses causal powers. Consequently, Stoics dismissed the idea of an incorporeal, immortal soul found in Platonic and Christian thought. The soul acts upon bodies, meaning it must itself be a body. Thus, it decays and dies like everything else, leading to profound theological implications.

However, the Stoics acknowledged that certain aspects—like time and place—do not fit into the category of being but are nonetheless part of reality. They included "sayables," or concepts expressible in language, alongside our thoughts. These do not exist in a corporeal sense but are considered to "subsist." Visually, this conceptual framework can be summarized as follows:

This approach is quite ingenious, as it allows the Stoics to be materialists while recognizing universal causality, all the while accommodating abstract ideas. It's challenging to find a more effective way to describe reality until we reach modern physics and philosophy, where Stoics still hold their ground.

The Two Cosmic Principles

The ancient Stoics believed that the universe is shaped by two principles: active and passive. The passive principle represents the foundational, inert matter, while the active principle, equated with God or Zeus, is responsible for transforming this inert matter into the observable world: mountains, flora, fauna, and humans.

Though this may suggest a dualistic worldview, the Stoics insisted that these principles are completely intertwined, separable only for discussion. Thus, their reality system is fundamentally monistic.

It's also vital to note that the divine principle interacts with inert matter through something called pneuma (breath). This manifests in various gradations, enabling different kinds of beings: the lowest level pertains to inanimate objects; a higher level characterizes plants; an even higher level applies to animals; and the highest level, the logos, distinguishes humans and the divine.

If this concept seems outdated, consider that modern string theory proposes that the universe consists of one type of entity: vibrating strings. The vibration frequency of each string imparts properties to what we identify as particles, which in turn constitute the macroscopic bodies we perceive. Just a thought...

Eternal Recurrence and the Living God

Stoic cosmology posits that the universe originated from a fiery explosion and will conclude with another, only to restart in a continuous cycle where everything repeats identically.

This notion may initially seem strange until we realize that even contemporary cosmologists have considered a cyclical universe, although this view is currently less mainstream.

According to the Stoics, each cycle would be the same because the divine does not alter its course; it always operates in the best manner possible. Modern cosmologists, however, would argue that each cycle differs due to beginning with a quantum singularity, an inherently random event that yields varied initial conditions each time.

On the topic of God: it exists (rather than merely subsisting), as it possesses causal powers and is consequently corporeal. God permeates the universe and guides its progression (providence). Furthermore, the divine/cosmic entity is a living organism endowed with universal reason (logos). In this sense, we are components of the cosmic organism, sharing in the logos.

Debates persist regarding whether the Stoics were pantheists or panentheists. Pantheism equates divinity with the cosmos, while panentheism suggests divinity exists within the cosmos yet transcends time and space. Based on these definitions, I believe the Stoics were pantheistic rather than panentheistic. However, this remains a point of contention and ultimately may be inconsequential.

Causality and Determinism

As previously noted, the Stoics embraced universal causality, categorizing existence only for entities with causal influence.

Their understanding of causality is deterministic: every occurrence is the result of preceding causes, with no exceptions or miracles. This view inevitably affects concepts like moral responsibility, which the Stoics sought to preserve.

They achieved this by adopting a position modern philosophers term "compatibilism" regarding free will— a term that was not part of philosophical discourse at the time, being more closely linked to Christianity's problems with evil. The most renowned illustration of their stance is Chrysippus’s cylinder and cone analogy:

> "[Chrysippus] resorts to his cylinder and cone: these cannot begin to move without a push; but once that has happened, he holds that it is thereafter through their own nature that the cylinder rolls and the cone spins. ‘Hence,’ he says, ‘just as the person who pushed the cylinder gave it its beginning of motion but not its capacity for rolling, likewise, although the impression encountered will print and, as it were, emblazon its appearance on the mind, assent will be in our power.’” (Cicero, De Fato, 43)

This analogy illustrates that both the cylinder and cone are subject to the same external force, yet they respond differently due to their inherent characteristics.

In parallel, humans react to both external and internal influences. When we say something is "up to us" (as Epictetus noted), we refer to internal causality. Critics of free will often misinterpret humans as marionettes manipulated by external events. In reality, we function as sophisticated decision-makers capable of responding to external stimuli with appropriate internal reactions. Unlike the cylinder and cone, we can also modify our internal nature—our character—by deliberately working on it through ongoing feedback loops. Remarkable!

The Stoics also addressed a prevalent argument aimed at challenging their determinism—the "lazy argument." This posited that if I am fated to recover from illness, why bother seeking medical help? Chrysippus countered that my recovery is co-fated; it results from numerous concurrent causes, including my decision to consult a doctor and take medication!

Psychology

Though we typically do not categorize psychology as a hard science or part of physics, the Stoics incorporated the study of the human mind into their broader understanding of nature, which seems fitting.

Their core idea was that the soul, being corporeal, is infused with a high degree of pneuma, enabling perception—something unique to animals but not to plants or inanimate objects. Such perceptions form the basis of what Stoics termed "impressions," or automatic judgments about the world. Depending on how we interpret a given impression, we experience an "impulse" or inclination to act in a certain manner. (Note that this does not imply acting impulsively; "impulse" is a technical term in Stoic psychology.)

For example, my dog perceives my approach with a leash and feels the impulse to rise from the couch in anticipation of a walk. Young children and unreflective adults respond similarly: impression > action.

However, reflective humans can engage in a more nuanced process: we can grant or withhold "assent" to an impression. This allows us to introduce reflection into the sequence, resulting in the following progression:

For instance, if I perceive that I am thirsty, an unreflective response might prompt me to get up and grab a beer from the refrigerator. However, I pause to consider that drinking beer at 11 AM while writing an essay is likely not my wisest choice. I can then choose to either refrain from acting on the impression or redirect it toward a glass of water, however mundane that may seem.

The capacity for assent distinguishes rational beings from everything else in existence, and according to Epictetus, this faculty is the only thing truly "up to us," defining our humanity. Hence, the most crucial of the three disciplines in Epictetean ethics is known as the "discipline of assent."

The cognitive ability that enables us to reason and to grant or deny assent to impressions is called prohairesis, and it is located anatomically in the hêgemonikon, which Marcus Aurelius refers to as the "ruling center" of our minds (the famed "inner citadel" of Pierre Hadot). While ancient Stoics believed the hêgemonikon resided in the heart (a claim later critiqued by Galen, Marcus’s physician), we would now identify it with the prefrontal cortex, facilitating what modern cognitive scientists describe as executive function.

Before concluding my discussion on Stoic physics, it's worth noting that the concepts of impressions, assent, and impulses frame Stoicism as a form of motivational cognitivism akin to Socratic thought, contrasting sharply with the views of Plato and Aristotle.

Socrates and the Stoics argued that wrongdoing stems from reasoning errors; had we known better, we would have acted rightly.

Conversely, Plato and Aristotle emphasized akrasia, or weakness of will, suggesting that we sometimes act based on non-rational motivations, such as desires or cravings.

Both perspectives resonate with me. While it's true that I occasionally struggle with willpower—convincing myself to stay home and watch TV instead of hitting the gym, despite knowing the latter is better—I can also evaluate my behavior through the Stoic lens. Clearly, I do not genuinely believe that going to the gym is the superior choice since it involves sacrificing a preferred activity for one I find less enjoyable. Although objective evidence might support the notion that gym attendance enhances my physical fitness, physical well-being isn't the sole priority in life.

Ultimately, one compelling reason to favor the Stoic framework is its alignment with contemporary cognitive science, which posits that there is no clear division between reason and emotion; both are integral components of our cognition and can influence one another. This understanding underpins the success of cognitive behavioral therapy.

[Next time: ancient Stoic logic!]