Aristotle's View of the Soul as the Form of the Body

Hylomorphism: The Unity of Matter and Form

Aristotle developed a philosophical framework called hylomorphism (from the Greek words hyle = matter, and morphe = form).

This is his general theory about how all things in the world are composed. According to Aristotle, everything that exists is a combination of two aspects:

• Matter – the physical stuff something is made of
• Form – the structure, organization, or essence that makes it what it is

For example: A bronze statue has matter (bronze) and form (the shape); a house has matter (bricks and wood) and form (the structure that makes it a shelter); a cake has matter (flour, eggs, sugar) and form (the recipe and structure that makes it a cake).

Neither matter nor form can exist alone. You can't have a statue-shape floating in the air without bronze. You can't have bronze being a statue without having a shape. They're inseparable.

Applying Hylomorphism to Human Beings

Aristotle applies this same framework to living things, including humans:

• The body = matter (the physical stuff we're made of)
• The soul = form (the organizing principle that makes us alive and human)

This is radically different from Plato's view. Plato thought the soul and body were two completely separate substances—the soul could exist on its own and was trapped in the body.

Aristotle says: No. The soul and body are not two separate things. They're inseparable aspects of one living human being. The soul is not a "thing" inside your body. The soul is what your body does—its life, its capacities, its functions.

What Is the Soul?

For Aristotle, the soul (Greek: psyche) is "the first actuality of a natural body that has life potentially".

This sounds complicated, but here's what it means:

• The soul is what makes a living body actually alive (rather than just potentially alive)
• The soul is the principle of life—it's what animates the body
• The soul is the set of capacities and functions that a living thing has

Without the soul, a body is just a corpse—just matter without life. With the soul, a body becomes an actual living organism.

The Soul Cannot Exist Without the Body

This is the crucial point: the soul and body are inseparable.

For Aristotle, asking "Can the soul exist without the body?" is like asking "Can the shape of a statue exist without the bronze?" or "Can the ability to chop exist without an axe?".

The answer is no. The form cannot exist without the matter.

When a body dies, the soul doesn't fly away to another realm. The soul simply ceases to exist because there's no longer a living body for it to be the form of.

A dead body is only a "body" in name. It's not really a body anymore—it's just decaying matter. Aristotle says a corpse is a body only "homonymously" (in name only), just like a carved stone eye is only called an "eye" but can't actually see.

The Axe Analogy

Aristotle gives a famous analogy to explain this:

Imagine an axe is a living thing. What would its "soul" be?

• The body (matter) of the axe = the wood and metal it's made from
• The soul (form) of the axe = its ability to chop, its function as an axe

If the axe loses its ability to chop—if the blade becomes completely blunt and useless—then it's no longer an axe. It's just wood and metal shaped like an axe. The "soul" of the axe (its chopping ability) has ceased to exist.

Similarly, your soul is what makes your body a living human body. It's your life, your capacities, your ability to think and feel and move. If your body dies, your soul doesn't continue somewhere else—it simply ceases to exist, just like the axe's chopping ability ceases when the axe is destroyed.

The Eye Analogy

Aristotle also uses the analogy of an eye:

What is the "soul" of an eye? Its ability to see.

If an eye loses its sight—if it becomes blind—it's no longer really an eye (except in name only). It's just a lump of tissue shaped like an eye.

Similarly, if a human body loses its soul (its life, its functions), it's no longer really a human body. It's just matter shaped like a body.

The seeing cannot exist without the eye. The soul cannot exist without the body.

The Hierarchy of Souls

Aristotle doesn't think all living things have the same kind of soul. He describes a hierarchy of souls:

1. Nutritive Soul (plants)

• Capacities: nutrition, growth, reproduction
• Plants have only this basic level of soul
• They can take in nutrients, grow, and reproduce, but nothing more

2. Sensitive Soul (animals)

• Capacities: everything plants have, PLUS sensation, perception, locomotion, desire
• Animals can sense the world, feel pleasure and pain, move around, and pursue what they want
• But they cannot reason or think abstractly

3. Rational Soul (humans)

• Capacities: everything animals have, PLUS reason, rational thought, intellect
• Humans can think abstractly, understand universal concepts, use logic, and pursue knowledge
• This is the highest form of soul

Notice the pattern: each higher level includes all the capacities of the lower levels, plus additional ones. Humans have all three: nutritive, sensitive, and rational capacities.

The Soul as Formal, Efficient, and Final Cause

Remember Aristotle's Four Causes? The soul plays three of these roles:

• Formal Cause – The soul is the essence or defining feature of a living body. It's what makes a human body human rather than just a lump of meat.
• Efficient Cause – The soul is the source of movement and change in the body. Your soul is what makes your heart beat, your lungs breathe, your limbs move.
• Final Cause – The soul is the purpose or goal of the body. The body exists for the sake of the soul's activities—thinking, perceiving, living.

Is the Soul Mortal or Immortal?

For most of the soul, Aristotle's answer is clear: the soul is mortal.

When the body dies, the soul dies with it. There is no afterlife for most of the soul. There is no reincarnation. When you die, you're simply gone.

However, Aristotle makes one puzzling exception: the intellect (specifically, the "active intellect" or nous).

He suggests that the rational part of the soul—the part that thinks about universal, eternal truths—might be separable from the body and might be immortal.

But this doesn't mean "you" survive death in any meaningful way. The active intellect is impersonal—it has no memories, no personality, no individual identity. It's more like an impersonal capacity for thought that exists eternally, not a personal soul that continues after death. So even if some aspect of intellect survives, Aristotle's view still entails that personal identity does not survive death.

Why Aristotle Rejects Plato's View

Aristotle explicitly rejects several of Plato's ideas about the soul:

1. The soul is NOT separable from the body. Plato thought the soul was imprisoned in the body and could escape. Aristotle says this is nonsense—the soul needs the body to exist.
2. Reincarnation is impossible. Plato believed in reincarnation—the soul moving from body to body. Aristotle ridicules this idea. He says a specific soul requires a specific body. A human soul can't inhabit a horse's body any more than the form of a table can suddenly become a chair.
3. The body is not a prison. Plato saw the body as a distraction and a prison. Aristotle sees the body as necessary for the soul to exist and function. The soul isn't trapped—it's the life of the body.
4. The soul is not a substance. Plato thought the soul was a substance—a thing that exists independently. Aristotle says the soul is a form, a capacity, a set of functions—not an independently existing thing.

The Stamp and Wax Analogy

Aristotle uses another powerful analogy: a stamp pressed into wax:

When you press a stamp into wax, you get an imprint—a shape. The imprint has no independent existence. You can't separate the imprint from the wax and have it float in the air. The imprint exists only as long as the wax maintains that shape.

This is the relationship between soul and body. The soul is like the imprint—it's the form imposed on the matter. It has no existence separable from the body, yet it gives life and structure to the body.

Why This Matters for Philosophy of Religion

Aristotle's view creates significant problems for traditional religious beliefs about the afterlife:

• If the soul cannot exist without the body, how can there be life after death?
• If the soul dies when the body dies, what happens to personal identity and consciousness?
• How can there be heaven, hell, judgment, or reward and punishment after death?

Medieval Christian philosophers like Thomas Aquinas tried to reconcile Aristotle's view with Christian belief in the resurrection. Aquinas argued that while the soul needs the body, God could miraculously preserve the soul after death until the final resurrection when souls are reunited with resurrected bodies.

But Aristotle himself offers no such solution. His view is that death is final for most of the soul.