Online College Courses for Credit

2 Tutorials that teach Aristotle on What There Is
Take your pick:
Aristotle on What There Is

Aristotle on What There Is

Author: Sophia Media

Identify, and apply, the central tenets of Aristotle's metaphysics and ontology.

See More
Fast, Free College Credit

Developing Effective Teams

Let's Ride
*No strings attached. This college course is 100% free and is worth 1 semester credit.

37 Sophia partners guarantee credit transfer.

299 Institutions have accepted or given pre-approval for credit transfer.

* The American Council on Education's College Credit Recommendation Service (ACE Credit®) has evaluated and recommended college credit for 33 of Sophia’s online courses. Many different colleges and universities consider ACE CREDIT recommendations in determining the applicability to their course and degree programs.


Video Transcription

Download PDF

Hello, and welcome to this tutorial on Aristotle's ontology and metaphysics. Today, we'll be discussing Aristotle's account of what there is, as well as his accounts of substance and essence. So let's get started where Aristotle says we should get started, with ontology.

Throughout history, philosophers have talked about what they called first philosophy. This is a pedagogical concept, indicating what must be studied first and learned in order to advance in the field of philosophy. Different philosophers have defended different candidates for what should be first philosophy. Many think that it is logic. It was said that Plato's rule was that none could enter the Academy until they had first mastered mathematics. Much later, Descartes said epistemology was first philosophy.

Aristotle, however, answered ontology. Ontology is the branch of metaphysics that examines the nature of being. As such, ontological questions focus on what kinds of things exist and how they exist. Does X exist without Y is an ontological question. Notice then, ontology appears to be a perfectly sensible candidate for first philosophy. If I want to make headway in any field, knowing what kinds of things exist seems like a helpful and natural place to begin.

This is especially important if you reflect on the nature of truth. What is it that makes a statement true? Most people would answer that a statement is true because it corresponds with reality in the proper way. What makes the statement Don is bald true? One would think it is because there exists a person named Don who finds himself in a state of being follically challenged. Hence, if our interest is in truth, then we must give an account of what there is.

Pause and think about an assertion such as this oven is hot. And what you would need in order to say that that statement is true. You would need to say there is an object. That it is an oven. And that it exists in a certain state.

But notice that we have asserted three things in saying that the oven is hot. There is a specific object that exists. That object is an oven. And that object, the oven, exists in the state of hotness.

But to assert these things, you need two concepts, the concept of oven and the state of being hot. And then you also need an existence claim. That this oven exists in that state. But let's set aside hotness for now, and just focus on the claims involved in saying there is an oven.

That is to say, there is something that exists, and it is an oven. So to say there is an oven is to say that this specific object, the oven, matches the general concept of oven. To say there is an oven, then, you therefore need this object, oven, and the concept, oven.

In philosophy, this is the difference between a particular and a universal. In philosophy, a particular is a concrete, extant entity. While a universal is an ontological category that is common to multiple particulars. These definitions are precise, if not the easiest to grasp.

Aristotle's own definition of a particular might be helpful here, as it is a little simpler than that just mentioned. Instead, he calls a particular a this, which seems vague and unhelpful until you stop and think about it. We can talk about oven, the universal which applies to multiple ovens, or this oven, the particular one in my kitchen. We can similarly talk about dog, or this dog, and so on.

But we can even talk about such a distinction with properties, such as the universal, blue, versus the particular, this blue. Hence, a this is actually a very helpful way to think about particulars. Take any concept for which you have a general term, such as sandwich, and put this in front of it, this sandwich. And you go from talking about the universal concept to a particular. But be careful. Notice that universal may be misleading, as it means more than one, rather than all or every.

All of this is to say if we grant that it is true that the oven is hot, we have said that three things exist, and therefore, entered three kinds of things into our ontology, particular ovens, the universal oven, and the universal quality of being hot. All three of these seem to be required in order to say that the simple statement, the oven is hot, is true.

Similar categories come up whenever we make a claim about truth. Consider claims like humans are rational. We posit particular humans, humanity, and rationality. As we continue to do this, however, we will begin to notice a pattern.

What we should notice is that any simple statement will have both a subject and a predicate. But this is not just a claim about grammar. In the sentence, the oven is hot, the particular oven is the subject while is hot is the predicate. While that is the case grammatically, such a sentence also describes a true state of affairs. Hence, the subject and predicate of grammar are intended to accurately mimic reality.

This is true in language, but similarly, in reality, we have both a thing and a property attributed to that thing. And accurately describing that the property belongs to that thing is to speak truly. Hence, our ontology has a collection of things of thises and thats. The technical term Aristotle uses to designate this category is substance, which designates any subject. Shoes, and ships, and sealing wax are substances, as are you and I. We also have ways those things can be, dented, adorable, fire-breathing, mauve.

Aristotle gives nine categories of types of ways things can be. There are quantities, such as 3.5. Qualities, such as handsome or green. Relations, like greater than, mother of. Places, in front of the TV. Times, like next month or noon. Positions, like sitting. States, such as unarmed or frenzied. Actions, such as reading. And affections, to be read.

Anything that can be said to exist will be one of these 10 categories, either a substance, or one of the other nine ways of being. However, in Aristotle's system, substance has ontological primacy over the other nine categories. This is to say a substance can exist without the other nine, but they cannot exist independently of substance. And hence, they are ontologically dependent on substance.

A simple example is that you can have a fender without a dent, but you cannot have a dent without a fender. Blueness cannot exist by itself. There are only blue things. Notice that by making individual substances ontologically primary, Aristotle has a significant disagreement with his mentor Plato.

Plato posited a form of goodness, for instance, that is independent of any individual good person. For Aristotle, however, there cannot be goodness without any good individuals, just as there cannot be dents without fenders. More generally, this connects to Aristotle's notion of essence. So let's talk about that now.

Take, as an example, the essence of humanity. Since it applies to multiple humans, it must be a universal. However, since you can truly assign properties to the universal humanity, such as saying, humanity is rational, the universal humanity must be substantial, according to Aristotle. But because humanity, like blueness, cannot exist independently as a floating property, the human essence, that is humanity, must exist in individual humans. Hence, unlike Plato, Aristotle looks for humanity inside of individual humans.

Plato had posited such an essence as a metaphysical entity, called a Form, that exists independently of individual humans in some type of Platonic Heaven. An Aristotelian essence, by contrast, is in a particular being. Humanity is not only set of individual humans as a predicate. But the essence of humanity is spatio-temporally located inside of each and every human. Hence, an Aristotelian essence is physically located in humans.

More generally, it is located in some specific stuff, one type of matter. This essence makes the thing, the stuff, what it is. So under Aristotle's conception, the essence inside of the matter is what causes the matter to be organized as a human, rather than as something else. It gives the matter form, in the lowercase sense of form, not to be confused with the Platonic Form.

As an example, consider a few hundred pounds of stuff, carbons, proteins, deoxyribonucleic acids, and the like. Does simply being a few pounds of organic stuff make it a human? No, it could just as easily be a bear, or a deer, or a pile of butchers leavings. Thus, the matter must be organized in a certain way. And it is this organization that makes it a human, rather than a deer, a bear, or anything else. In sum, since how the stuff is organized determines what it is, and what makes a thing what it is is its essence, we can see that the organization must be a product of its essence.

And while essences can and do get tricky, Aristotle's ontology gives us an easy trick for identifying an essence, of quickly identifying that which Plato agonized over. If we want to discover and describe the human essence, all we need to do is isolate two things, a genus and a differentia. The genus tells us what kind of thing it is. The differentia tells us what sets it apart from other things of the same kind.

Before turning to humans, let's try a few simple examples of identifying an essence via the method of genus and differentia. Say I wanted to identify the essence of a hammer. I'd ask, what kind of thing is it? My answer, the genus, would be that it is a tool. I might then ask, what distinguishes hammers from other tools? My answer, the differentia, might be that they are used for pounding. Hence, the essence of a hammer, that is, what makes a hammer a hammer, is that it is a tool used for pounding.

Let's try another example and identify the essence of a square. What kind of thing is a square? A square is a rectangle. What distinguishes squares from other rectangles? They have equal sides. Hence, to be a square is essentially to be an equal-sided rectangle.

And notice that, in identifying a genus, my goal is to go up one step. For instance, if I said, the genus of a square was shape, and I asked what separates squares from other shapes, I would have to say several things, four-sided, right angles, et cetera. If you find yourself giving multiple differentia, it's because you went up several steps. Every one step should have one differentia.

So what kind of thing is a human? A human is a biped, that is something that walks on two legs. What separates humans from other bipeds? According to Aristotle, rationality, in the sense of being able to think abstractly. That's what separates humans from other bipeds. Hence, a human is a rational biped, or a rational animal, depending on whether Aristotle was writing about philosophy or biology. That is the human essence.

If all this sounds familiar, it is because we still use Aristotle's concept in biology. Using binomial nomenclature, an organism may be identified by giving its genus and species. Homo sapiens is Latin for rational biped, or wise man, distinguishing them from Neanderthal, Cro-Magnon, and other hominids. Hence, we still use genus and differentia to figure out what kind of thing an organism is.

But pause and let that sink in. Can you think of anything else that has continued to prove useful in science for over 2000 years? The fact that has withstood the test of time tells you there is certainly something of value here.

So now, let's use our human example and get a little more detailed into Aristotle's metaphysics. What is a human, then? As we have seen, according to Aristotle, a human is a union of form, that is essence, and matter. This is a view called hylomorphism. Hylomorphism is the metaphysical theory that posits being as a union of form and matter. And this gives us a start of the view, but more needs to be said.

First, although we have been using humans as an example, this is Aristotle's theory of being, and therefore, applies to everything, that is to every substance in the Aristotelian sense of substance, any subject, animal, vegetable, or mineral, any individual item that is an instance of a natural kind or species, in Aristotle's sense. Second, as a theory of being, it maintains an intimate, maybe even essential relation. Aristotle's view here is that existence must be a package deal. You don't have formless matter sitting around waiting to be shaped, but instead, you get both or none at all. There is not formless matter, even though we can talk about it conceptually. And in doing so, call it prime matter.

But on the flip side, there is not matterless form either. There is no such thing as humanity independent of individual humans, once again, contra Plato. Aristotle explains this through an analogy with wax. Conceptually, we can separate wax into its matter, the stuff of which it is composed, and its shape. But this distinction is purely conceptual. There is no such thing as shapeless wax in the sense of having absolutely no shape whatsoever. And there is likewise no such thing as shape in general without something being shaped.

Given this brief presentation of Aristotle's view, we can already see that there will be some interpretive difficulties. First, we must wonder about the nature of the form. Is the form of a living thing just its structure, some blueprint for producing humans, much like how we think of the genetic code provided by DNA? Or is there something more than this?

In living things, Aristotle equates form with soul. However, we need to be careful. Aristotle did not use the word soul in the familiar way we generally use it today. The ancient Greek word he uses is anima, which is etymologically related to both animal and animate. Aristotle's notion of soul, or anima, is simply whatever makes a living thing alive. As such, it is perhaps best understood as an animating force.

When it's considered in this way, it is clear that Aristotle is not trying to give quasi-religious accounts of human souls, and does not seem to hold out much hope of an afterlife. But that only tells us what it is not. We know souls provide an organizing principle. It's not clear what else, if anything, they do.

All right, so let's recap. In this tutorial, we learned that Aristotle held that first philosophy was ontology. As the ground for being, he posited 10 categories of being, out of which substance was primary. One important kind of substance is species, which is universal and exists in particulars. An easy way to identify a species is to discover the genus and differentia. Essences, as form, fit into Aristotle's hylomorphic account of being. A being is a special union between form and matter. Thanks for watching. And we'll see you next time.

Terms to Know

The metaphysical theory that posits being as a union of form and matter


The branch of metaphysics that examines the nature of being


A concrete, extant entity


An ontological category that is common to multiple particulars