Aristotle and Mentalism [Why He Was WRONG]

You will most likely agree that much has changed since the days of Aristotle and mentalism when it comes to the way we view neuroscience and complex behaviors.

We now view human nature in a completely different light…


To understand our advancements in science and our knowledge of complex human behavior, we must have a clear grasp of the modern idea of the “mind” and from where it originates.

Aristotle got people thinking about the brain…

…but he also made one colossal mistake when he first formulated his theory of the human psyche.

Now, we are going to go over what he thought was controlling our behavior, where he was wrong, and what we know to be true so that you can think about human nature in a way that is harmonious with modern neuroscience.

Read on.

The Life and Death of Aristotle

The Life and Death of Aristotle.

“Sometimes people don’t want to hear the truth because they don’t want their illusions destroyed.”

Friedrich Nietzsche.
A picture of Aristotle, the philosopher.

In 384 B.C in the ancient city Stageira, Aristotle was born into a medical family.

His father, Nicomachus, was a personal physician to Amyntas II, the King of Macedonia.

Then suddenly, when Aristotle was still a young boy, his father passed away, leaving his son to fend for himself.

In the years following this great tragedy, Athens had grown to become the heart of higher education.

At the age of 17, Aristotle was sent there to pursue a life in academia.

A picture of Plato and Aristotle.
Source: Wikimedia Commons

Once in Athens, he soon found himself studying under the tutelage of one of Socrates’ most exemplary scholars, namely Plato. 

Aristotle quickly developed a deep and valuable relationship with Plato, who was the director of the Academy; they became master and apprentice.

Soon, Aristotle began conjuring up plans to become Plato’s successor.

However, something strange had begun to stir the young student from deep within, making him feel a slight pull in a different direction than that of his master.

After more than two decades of maintaining a stable relationship with Plato and his Academy, Aristotle began developing his own ideas, philosophical thinking, and concepts of teaching.

Aristotle’s Turning Point

Al maestro cuchillada — to the master goes the knife. A quote that talks about what Aristotle did to Plato.

The young student began disagreeing with his master’s teachings and his dogmatic philosophical beliefs.

Plato didn’t seem as prominent and awe-inspiring anymore, making Aristotle distance himself from his teacher.

The word of this impending conflict spread like wildfire through the Academy.

A painting of Plato and Aristotle, plus more of Plato's students in the Academy.
Source: Wikipedia

Yet, in 347 B.C when Plato died, it came as a surprise to Aristotle that he didn’t inherit the director’s seat, as had been his grand vision all along.

Instead, it went to Plato’s nephew, ultimately crushing Aristotle’s dreams of running the Platonic Academy.

To escape this academic dead-end, he cut ties with the Academy and left Athens.

Finally free from the overbearing demands and restrictions from academia, Aristotle soon discovered some latent inclinations for studying biology that he poured all his energies into exploring.

These inclinations had been stirring inside him since his ideas had begun deviating from those of his master.

Now, he could finally realize his full potential in life.

The Rise of Alexander The Great

Aristotle talking to Alexander The Great.
Source: Wikimedia Commons

In 338 B.C, King Philip II’s son, Alexander the Great had just turned 13 and needed a private tutor.

By this time, Aristotle had reached great intellectual stature, which ultimately attracted Philip II’s attention.

Aristotle moved to Macedonia to tutor the young conquerer until Alexander finally couldn’t see any future in his academic studies.

In 335 B.C, Aristotle returned to Athens to, with Alexander’s permission, start his own school.

By this time, Plato’s Academy was still considered the most influential place for education in Greece, having reached a sovereign position of intellectual authority.

  • To challenge this, Aristotle started Lyceum.

In the following years, he wrote his most seminal papers and began deepening his interest in biology.

Lyceum was kept alive by Alexander’s fundings, while also receiving specimens from him that Aristotle and his students studied closely.

By this time, the great Hellenistic philosophers had begun debating what mediated behavior, sensation, and consciousness.

The medical theorist, Alcmaeon of Croton (c. 540–500 B.C), was a pioneer in the field, concluding that the brain had the dominant role in controlling human action.

A picture of Hippocrates.
Source: Wikimedia Commons

The Greek physician, Hippocrates (c. 460 – c. 370 B.C), ultimately came to the same conclusion, saying that:

“It ought to be generally known that the source of our pleasure, merriment, laughter, and amusement, as of our grief, pain, anxiety, and tears, is none other than the brain.”

Aristotle’s School of Thought

A Marcus Aurelius quote: "To accept without arrogance, to let it go with indifference."

Having started Lyceum, and attained high status in academia, Aristotle eagerly wanted to add to the discussion his own scientific conclusions.

What he discovered, however, contradicted his predecessors’ findings:

Instead of attributing human nature to the brain, Aristotle concluded that the heart was the source of sensation and movement.

The heart, he argued, was the seat of all thought and reason, claiming that the arteries and the heart were what controlled cognition and behavior.

  • His contemporaries soon opposed his findings.

Still, Aristotle persisted and stubbornly pressed on, going out of his way to prove his point. 

Aristotle demonstrated, through dissections, that the human sensors were connected to the heart through blood vessels — or phlébia.

He went on to say that touch and taste were “evidently connected to the heart.”

A picture of ancient Athens where Aristotle taught the ideas of mentalism.
Source: Wikimedia Commons

This caused heated debates among the philosophers who argued against Aristotle’s empirical findings, which only made Aristotle more tenacious. 

Then suddenly, as the arguments reached new heights, Alexander the Great died under strange circumstances, and the Macedonian government was overthrown.

This led to Aristotle getting charged with impiety and was sentenced to death for his association with his former student.

To avoid brutal execution, Aristotle, once again, fled Athens and ended up in Chalcis on the island of Euboea.

He remained there until he died a year later, in 322 B.C, from an organ disease, still believing his own hypothesis, leaving his pre-neuroscientific studies incomplete and open for violent debates.

Aristotle’s Life — In-depth analysis

Aristotle's life - in-depth analysis of mentalism and his philosophy.

To the masses, Aristotle was known as “The Philosopher.”

The great intellectual who trained under Plato, and dedicated his entire life to mastering science and teaching his ways to the ambitious youth.

His seminal writings influenced and started numerous fields of science:

  • He was considered one of the most skilled biologists of all time
  • He is thought of as the founder of modern anatomy
  • A pioneer in the field of embryology
  • The original taxonomist
  • The first evolutionist
  • The one who systematized the study of animal behavior
  • The precursor to biogeography, and had a significant influence on the school of economics, and politics

Aristotle’s findings also marked the beginning of modern psychology

He also had a public persona that spoke of him as a relentless survivor:

Aristotle survived the death of his parents at a young age, as his mother also passed away early in his life.

He trained under the most prominent intellectuals of his time, and eventually became one of the most respected and influential thinkers in human history.

Even though he was a highly admired, eminent writer and teacher — and paved the way for what we today call neuroscience — something about the way he viewed human behavior and its biological underpinnings seem to have moved his work into the shadows of oblivion.

Aristotle’s Mistake and the Contemporary Philosophers

A quote from this article about mentalism and the philosopher Aristotle.

Years before the rise of Aristotle, Alcmaeon came to the conclusion that the brain (Ἐγκέφαλος) had the leading role in controlling sensation, movement, and in mediating behavior.

The Hippocratic doctors eventually ended up agreeing with Alcmaeon’s findings as their empirical studies showed the same results.

What, then, spelled Aristotle’s demise was his systematic denial of his predecessor’s findings in favor of his own; Aristotle maintained that the brain played but a small role in controlling and executing human behavior.

  • His stubbornness, however, eventually became his fall.

He would argue against Hippocrates’s, and Alcmaeon’s findings, saying that they had “fallacious” opinions on what caused sensations, movements, and complex behaviors.

Even Plato came to the conclusion that the brain was the superior force behind human action, which Aristotle, also, went against — perhaps out of spite and to deviate even further from his former master.

The contemporary philosophers soon argued that the scarcity of flesh around the brain was there for sensation to get through.

  • Aristotle tirelessly opposed their claims:

He, instead, maintained that the fleshiness was there for the brain’s cooling function; Aristotle believed that the heart was warm because it was the most productive part of the body and the one most full with superior intelligence.

The brain, then, was cool to counterbalance the heat from the heart so that humans could find an equilibrium, a perfect spot, that was optimal for mental activity and philosophical thinking.

He believed that the brain played a subordinary role in the “heart-brain” system when it came to sensation; it was second to the heart.

Aristotle’s Intellectual Antagonists

A quote from Aldous Huxley: "Facts do not cease to exist because they are ignored."

To pollute the discussion further, Aristotle would go on to say that the back of the head was fleshless; you couldn’t find any sensory organs there.

His intellectual antagonists claimed that the sense organs were placed near the brain, but Aristotle fought back, giving several reasons for taking a stand against their claims:

One of them was that the eyes were facing forward so that we could see along the line we are moving, and that “it is reasonable enough that the eyes should always be located near the brain, for the brain is fluid and cold, and the sense organ of sight is identical in its nature with water.”

Athens in black and white.
Source: Wikimedia Commons

His way of thinking, together with his unwillingness to entertain contradictory explanations, drove him further away from his intellectual rivals and shielded him from conflicting opinions about human nature and the brain.

It became more about showing who was right rather than the pursuit of truth, which by its very nature tore down more than it helped build.

The Signs From Childhood

A Robert Greene quote: "If we learn to handle criticism well, it can strengthen us and help us become aware of flaws in our work." From Mastery.

Aristotle’s aversive behavior toward contradictory findings didn’t suddenly arise out of nowhere:

  • These signs were traceable back to his childhood.

Despite, or perhaps because of, his father’s profession, Aristotle never showed an interest in reading the medical literature.

Out of all the areas that interested him, this was not one of them; he was never au courant with what was considered modern medical knowledge.

This systematic avoidance of his father’s field of expertise, the need to prove himself through endless debates with his adversaries, and the denial of the brain’s role in human behavior eventually ended up being detriments to his sustained influence in the field of neuroscience.

  • Leaving him, and his work, behind.

In the end, Aristotle went to his grave believing the story of his own brilliance — never learning the truth about human nature.

A Historical Analysis of Aristotle

A quote that talks about Aristotle's legacy and how mentalism wasn't worthless for the advancements in science.

It’s easy to blame Aristotle for his obstinacy.

In reality, he was far from the only person having erroneous ideas about the mechanics of the brain:

The philosopher Empedocles thought that the “medium of thought” was at the center of the heart; he believed that it made human intelligence blood-dependent and that the blood composition had something to do with knowledge and intellect.

A painting of Empedocles, who also believed in mentalism and Aristotle.
Source: Wikimedia Commons

This also meant that he envisioned a world where the heart was the center for mental disorders and that everything we now associate with the brain was the workings of the heart.

This idea was also common in ancient Egypt, as well in Mesopotamian, Babylonian, and Indian scientific thinking at the time.

It was also common to completely ignore the brain in ancient Chinese medical practices, which didn’t change until 1595 after Matteo Ricci published his writings.

A picture of Matteo Ricci.
Source: WIkimedia Commons
  • Aristotle was a biologist in the purest form, not an applied one.

In his day, the methodology of biology was incapable of yielding the correct view of the brain’s role in complex behavior; his view of the brain completely lacked the anatomical, physiological, and introspective evidence to support his claims.

This, together with his stubbornness, made it an impossible task for him to fully assess the brain’s importance in mediating behavior.

Aristotle’s Academic Legacy

A quote from Criss Jami that fits perfectly with Mentalism: "Pride and power fall when the person falls, but discoveries of truth form legacies that can be built upon for generations."

Not everything he did was a detriment to his enduring scientific influence:

Aristotle’s ideas, and the way he stressed the importance of dissection encouraged other scientists to perform anatomical studies.

His work created an interest in studying the brain, and to explore further possibilities.

It eventually led to the start of neuroanatomy at the magnificent Museum at Alexandria.

It was in the shadow of Aristotle’s advancements that the great museum anatomists, Herophilus and Erasistratus, began to systematically study the structure of the human body.

A picture of the Museum at Alexandria and its library where the philosophers took the work of Aristotle and mentalism further.
Source: Wikipedia

Through their work, they soon provided the world with the first detailed, and accurate description of the brain.

Shortly after their findings were published, the brain’s superior role in mediating behavior was no longer in question.

Even though everything seemed to move in the right direction, there was, however, one concept that lingered and had a bitter taste that would come to influence both religious movements and the earliest stages of the neuroscientific studies:

Namely, what Aristotle called the “psyche” — or the mind.

Aristotle’s Hypothesis of The Human Psyche

A mentalism quote from the article.

The hypothesis that the human mind controls our behaviors can be found in the ancient Greco-Roman mythology, taking us back more than 2000 years in time.

Written in the 2nd century A.D, the story of the Psyche originates from Metamorphoses where the mortal Psyche becomes the wife of the god Cupid.

Cupid’s mother, Venus, opposes the marriage, harassing Psyche with near-impossible tasks and obstacles to overcome.

Through sheer persistence and relentless commitment, Psyche comes out victorious and is made immortal, removing all of Venus’s objections to the marriage, allowing the couple to live together as one for all eternity.

Psyche and Cupid together, which is a story that Aristotle used when creating mentalism.
Source: Wikimedia Commons

Aristotle alluded to this story when he created his hypothesis of the human psyche:

The idea that all of our intellectual functions were produced by the mind — or the soul.

This marked the beginning of the study of psychology.

In this new branch of science, though, the brain played no role.

The Psychology of Mentalism

A Carl G. Jung quote: "I shall not commit the fashionable stupidity of regarding everything I cannot explain as a fraud."

To the Greek philosopher, the psyche was a non-material entity responsible for mediating consciousness, desires, and reason, but doing so independently of the body.

The mind, Aristotle argued, was something inside us; an entity that is “in our brain but not of our brain.

A self that was more than our fundamental biological building blocks, reacting to our biology, while also being immune to its impulses.

From the way we imagined things to our emotional life, Aristotle argued that this was the workings of this non-material entity, this non-biological self.

To the philosopher, the psyche was more of a spiritual being that controlled us rather than pure biology:

It was the voice in our head that influenced our choices and morals in life, giving us free will over our actions, unaffected by external and internal influences.

The word psyche was translated into the Anglo-Saxon word we use for memory, namely mind, which then turned into Aristotle’s idea of what mediated behavior through mentalism.

This concept was later adopted by Christianity, where it was believed that this non-material entity controlled our actions and that our essential consciousness lived past our death, and on some level came from an almighty God.

A God, whose workings were mysterious and beyond our comprehension; a belief we today, to a great extent, can attribute to people who were suffering from schizophrenia.

Mentalism Becomes Dualism

A quote from the blog post that talks about mentalism and the philosophy of it.

In philosophy, this belief is called mentalism.

At the time, it made perfect sense, but the main problem with mentalism is that is doesn’t make the mind-body connection.

Something that René Descartes (March 31, 1596 — February 11, 1650) discovered through dualism, which sparked controversy and came with its own scientific errors.

A picture of René Descartes.
Source: Wikimedia Commons

This reveals that if Aristotle had infact believed that the brain was the superior mediator of human behavior, it would still have meant nothing because mentalism left him with the idea that a biological organ can’t produce actions on its own.

Aristotle’s view, then, was that this non-material entity, the psyche, was, independent of the body, the sovereign ruler of behavior.

He believed that our consciousness lived past our death, and gave us free will, while simultaneously controlling us independently of our biology — which is a remarkable paradox.

Although mentalism has had a significant influence on modern behavioral studies because the terminology in psychology builds on words — consciousness, memory, motivation, etc. — that originate from Aristotle’s work, its “empirical underpinnings” don’t hold up in contemporary science.

Today, we have a more clear and precise understanding of the human brain; we know that a non-material entity can’t possibly mediate our behaviors; we are the sum of our biology, not mentalism and its fundamental ideas.

For this reason, somewhere along the road, we abandoned mentalism to make way for a better model for explaining behavior.

Namely materialism.

Behavioral Neuroscience, Aristotle, and Mentalism

“I love science, and it pains me to think that so many are terrified of the subject or feel that choosing science means you cannot also choose compassion, or the arts, or be awed by nature. Science is not meant to cure us of mystery, but to reinvent and reinvigorate it.”
― Robert Sapolsky

After Aristotle’s rise and fall in science, and when Descartes’ theory came and went, another brain-behavior theory came into existence:

  • Materialism.

By the mid-nineteenth century, the concept that built on the predecessors’ findings continued to map together the body with the nervous system as a way to explain human nature and complex behaviors.

This theory developed its backbone through the findings of Alfred Russel Wallace and Charles Darwin: evolution theory and natural selection.

Arriving at the same conclusion, the concept that all living species are related, at roughly the same time, Darwin and Wallace latched their intellectual claws into the public’s eye and made it unmistakably evident that there are common anatomical and behavioral patterns across species, despite their diversity.

This also paved the way for a deeper understanding and a complete acceptance of the interplay between the brain and the nervous system in mediating behavior and creating what we call human nature.

Now, contemporary neuroscientists subscribe to materialism as the strategy to explain human nature, while using the terminology from Aristotle and mentalism when using words such as consciousness, pain, and memory to describe the profound mechanics of our being, the “self.”

Without imagining that there are non-material entities that are in our brain but not of our brain.

Ostinato Rigore and Mentalism

The last quote from the article about Aristotle and mentalism.

Materialism, then, is the objective, measurable, and empirical model for studying and mastering the complexities of human behavior.

Even if Aristotle was wrong when he fought to the death trying to defend his findings, through the lens of mentalism (that the heart was the center of social behavior), his methodology, and his endless rigor — or ostinato rigore as Leonardo Da Vinci called it — eventually led to the birth of modern neuroscience.

And, ultimately, to everything we know about the human body and the workings of the brain. 

  • Finally:

You can dismiss the use of obsolete tools in favor of better ones while maintaining a clear and precise historical understanding of how the old ones were indeed necessary for us to create new and better tools.

To completely ignore Aristotle based entirely on how he ended up with a distorted view of the mind is to ignore the broader perspective on the history of scientific advancement, and ignoring history is the most devastating mistake we can ever make.

Summary: Materialism, Mentalism, Aristotle, and Modern Neuroscience

Summary header
The life of Aristotle.
  • Mentalism views human nature through the lens that there is an intangible, non-material entity called the mind, or psyche, controlling our behavior — the brain plays a secondary role in mediating our actions, which explains nothing.
  • Aristotle, through mentalism, thought that the heart was the center of human behavior and that the brain was secondary in stirring us into action.
  • Materialism, the concept that the brain is the superior mediator of human behavior, is what drives modern research in all the fields of neuroscience.
  • The support for materialism as the right lens through which to study the brain comes from natural selection and evolution theory.
  • The discovery of genes and how they affect human behavior further supports materialism as the correct strategy for studying neuroscience.
  • All modern neuroscientists subscribe to the theory of evolution and the principle that all living organisms are descendants from a common ancestor, and that there exists a similar pattern of every animal’s nervous system.
  • Don’t dismiss history because the scientists were wrong, see instead how their failures and methods ultimately led us to where we are today.
  • Learn from history, don’t dismiss it.

P.S. Since you don’t want to dismiss the lessons from history, you should check out our newsletter because we send out lessons on human nature straight to your inbox.


Originally published: 2019-08-07
Editor: Ida Kemell, M.Sc.


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