Aristotle’s Metaphysics: Unveiling the Nature of Being

What does it mean to simply be? This question sounds almost too simple to take seriously – and yet it drove one of the most ambitious intellectual projects in the history of Western thought. Aristotle, writing in the fourth century BCE, decided that no specialized science – physics, mathematics, biology – could answer it properly, because each of them only studies a slice of reality. He wanted a discipline that examined existence itself, without restriction. He called it first philosophy. We call it metaphysics.

Why Aristotle called it “first philosophy” 🔗

The label metaphysics is, technically, an accident of history. Early editors of Aristotle’s manuscripts placed these texts after (meta) his Physics in the canonical arrangement of his works, and the name stuck. But Aristotle himself consistently referred to the discipline as first philosophy – the foundational science that precedes all others, because it investigates the principles and causes on which every other inquiry ultimately rests.

According to Wikipedia’s overview of the Metaphysics, Aristotle considered first philosophy superior to all other theoretical sciences because it is concerned with the ultimate causes of all reality, not just the secondary causes of some portion of it. A physicist studies nature insofar as things are subject to change. A mathematician studies things insofar as they are countable and measurable. The metaphysician, by contrast, steps back from these specific angles and asks about being itself – with no limiting qualification at all.

Being qua being: what does that actually mean? 🔗

The phrase being qua being (to on hē on in Greek) is Aristotle’s signature formulation for the subject matter of first philosophy, and it is frequently misunderstood. It does not name some exotic entity called “being qua being.” The Latin word qua means “insofar as” or “under the aspect of.” So the phrase simply means: a study of things as beings, in the most general sense possible, without reducing them to their physical, mathematical, or any other specialized aspect.

As the Stanford Encyclopedia of Philosophy explains, first philosophy is not the only discipline to study beings – but it is the only one that studies them purely as beings, rather than under some particular description. Every other science narrows its gaze. Metaphysics alone keeps it fully open.

Central to this broad inquiry is the concept of substance (ousia). In his earlier work, the Categories, Aristotle had already argued that beings fall into ten distinct categories – substance, quality, quantity, relation, and others – and that substance holds a privileged position among them all. When we say “Socrates is pale” or “Socrates is six feet tall,” we are attributing qualities and quantities to Socrates. But Socrates himself, the substance, is what stands independently. As one accessible introduction to Aristotle’s metaphysics puts it: substance is that which all other categories refer to, and it can exist without them, while they cannot exist without it.

The break from Plato: forms come down to earth 🔗

To understand why Aristotle’s metaphysics mattered, it helps to see what he was arguing against. His teacher Plato had proposed that the truest reality lies not in the physical world but in an abstract realm of Forms – perfect, eternal, unchanging blueprints. The Form of Beauty, the Form of Justice, the Form of the Triangle: these were, for Plato, more real than any beautiful face, just act, or drawn triangle you could encounter in the world. Physical objects merely “participate” in these transcendent Forms; they are pale imitations of the real thing.

Aristotle found this deeply unsatisfying. If Forms are the essences of things – what makes a dog a dog, or a tree a tree – then those essences must be in things, not hovering in some separate realm above them. New World Encyclopedia’s entry on form and matter captures Aristotle’s objection precisely: how could a separate, non-physical Form truly explain the concrete existence of a physical object? The explanation is supposed to make the thing intelligible, but a Form marooned in another world seems causally inert with respect to the thing it is meant to explain.

This criticism led Aristotle to develop hylomorphism – from the Greek hyle (matter) and morphe (form). Every physical substance, on this view, is a compound of two intrinsic principles: matter and form. They are never truly separate. You never encounter formless matter or matterless form in the natural world. What you encounter is always this particular compound: a bronze statue, a living oak, a human body.

Matter and form: the two principles of every substance 🔗

Matter (hyle) is the indeterminate “stuff” out of which something is composed – the clay, the wood, the flesh. On its own, matter is pure potential; it has no fixed identity. Form (morphe or eidos) is the organizing principle that gives matter its specific structure, function, and identity. As IAS Express’s module on Aristotle explains, form is the principle of determination and actuality, while matter is the principle of indeterminacy and potentiality.

Crucially, Aristotle grants form priority over matter. Form is what makes a thing the kind of thing it is. The wood matters less than the arrangement of the wood: a heap of timber is not yet a house; a house requires the form of shelter – rooms, walls, a roof in the right configuration. Strip away the form and you no longer have the thing; you just have material. The Stanford Encyclopedia’s entry on form and matter notes that Aristotle introduces this distinction specifically to explain how things come into existence without violating the principle that nothing comes from nothing: matter persists through change, while form is acquired or lost.

Potentiality and actuality: explaining change 🔗

The matter-form distinction is essentially a snapshot of a substance at any given moment. But Aristotle also needed to explain how things change – and here he introduced one of his most influential conceptual pairs: potentiality (dunamis) and actuality (energeia or entelecheia).

This pair solved a genuine philosophical crisis. The pre-Socratic philosopher Parmenides had argued that change is logically impossible: a thing either is, or it is not – and something cannot move from non-being into being. Aristotle’s solution, as Florida International University’s notes on Aristotle summarize it, is to distinguish between a potential being and an actual being. Change is not a leap from nothing into something – it is the actualization of a pre-existing potentiality.

An acorn is actually an acorn but potentially an oak tree. The oak tree is the actualization of what the acorn was all along capable of becoming. A block of marble is potentially a statue; once sculpted, the statue is actual. Matter is always linked with potentiality; form is linked with actuality. Wikipedia’s entry on potentiality and actuality cites Aristotle directly on this point: matter exists potentially because it may attain form, and when it exists actually, it is then in the form.

Importantly, for Aristotle, actuality is prior to potentiality – not just logically, but in substance. The finished oak is more fully real than the dormant acorn; the sculpted statue is more real than the uncarved marble. As Bryn Mawr Classical Review’s discussion of Aristotle’s Metaphysics IX notes, Aristotle establishes a hierarchy among ways of being, arguing that actualities are prior to and more complete than their corresponding potentialities.

The four causes: a complete account of any change 🔗

Potentiality becoming actuality always has an explanation – and Aristotle insists that a complete explanation requires not one but four distinct types of cause. Using the example of a bronze statue:

• The material cause is what the statue is made of: bronze.
• The formal cause is the essence or defining structure: the particular shape and features of the figure.
• The efficient cause is what initiated the process: the sculptor and her tools.
• The final cause is the purpose or goal: the completed artwork, or perhaps the commemoration it was made to achieve.

As Philoparadoxia’s detailed analysis points out, Aristotle was the first philosopher to articulate the final cause explicitly. Earlier thinkers had identified one or more of the other three, but none had systematically recognized that every natural process is oriented toward a goal – an idea Aristotle called teleology. Every acorn is not just capable of becoming an oak; it is, in a sense, aimed at becoming one. The goal is internal to the thing, not imposed from outside.

The unmoved mover: where first philosophy meets theology 🔗

If everything that changes is moved by something else – if every actualization of a potentiality requires a mover – then there must be something that starts the entire chain without itself being moved. Otherwise, you face an infinite regress with no starting point. Aristotle’s solution is the unmoved mover (proton kinoun akineton): an eternal, immaterial substance that causes all motion and change in the universe while remaining entirely unchanged itself.

Wikipedia’s entry on the unmoved mover explains that this being is pure actuality – it contains no potentiality whatsoever, because any potentiality would imply the possibility of not acting, which would break the chain of eternal motion. It moves everything else not by pushing or pulling, but by being the ultimate object of striving and desire: everything in the cosmos orients itself toward this perfect, self-sufficient being the way a final cause draws things toward completion. Aristotle describes its activity as “thought thinking itself” – pure intellectual self-contemplation, with no remainder of materiality or unrealized potential.

This was a genuinely philosophical, not religious, argument. Aristotle arrived at the unmoved mover through the logic of his own metaphysical system, not through theology. Still, the concept proved enormously influential: Britannica’s entry on hylomorphism notes that Thomas Aquinas later gave a full account of Aristotle’s hylomorphism in his own theological writings, and medieval scholars from Avicenna to Averroes found in Aristotle’s first philosophy a rigorous framework for thinking about God, creation, and the structure of reality.

Why Aristotle’s metaphysics still matters 🔗

Aristotle’s first philosophy established the vocabulary and the questions that would shape Western metaphysics for more than two thousand years. The distinction between matter and form reappears in Aquinas’s theology, in Renaissance natural philosophy, and even in contemporary philosophy of mind debates about what makes a physical system a thinking one. The potentiality-actuality framework anticipated modern discussions of dispositions, capacities, and modal possibility. Britannica points out that twentieth-century physics – with its notion of elementary particles as “tendencies to exist” – has brought the questions Aristotle’s hylomorphism was designed to solve back into serious scientific discussion.

More broadly, Aristotle’s insistence that reality must be explained in terms of what things are, what they are made of, what produced them, and what they are for remains a powerful template for explanation in any domain. His decision to ground metaphysics in the tangible, observable world – rather than in a separate realm of abstract Forms – was a move toward the kind of empirical seriousness that would eventually animate modern science.

What do you think? If form is what makes a thing what it truly is, does Aristotle’s rejection of Plato’s abstract Forms actually bring us closer to understanding reality – or does grounding everything in the physical world leave some dimensions of existence unexplained? And when Aristotle argues that actuality is more real than potentiality, what does that imply about how we should think about human beings: are we defined more by what we are right now, or by what we are still capable of becoming?

References

1. https://en.wikipedia.org/wiki/Metaphysics_(Aristotle)
2. https://plato.stanford.edu/entries/aristotle-metaphysics/
3. https://open.library.okstate.edu/introphilosophy/chapter/__unknown__/
4. https://www.newworldencyclopedia.org/entry/Form_and_Matter
5. https://www.iasexpress.net/modules/1-7-actuality-and-potentiality-in-aristotles-philosophy/
6. https://plato.stanford.edu/entries/form-matter/
7. https://faculty.fiu.edu/~harrisk/Notes/Epistemology%20and%20Metaphysics/Aristotle's%20Metaphysics%20and%20Epistemology.htm
8. https://en.wikipedia.org/wiki/Potentiality_and_actuality
9. https://bmcr.brynmawr.edu/2003/2003.07.47/
10. https://philoparadoxia.com/aristotle-metaphysics-substance-form-matter-four-causes-teleology/
11. https://en.wikipedia.org/wiki/Unmoved_mover
12. https://www.britannica.com/topic/hylomorphism