Plato and Aristotle: Crash Course History of Science #3

Summary

This episode of Crash Course History of Science explores the philosophical foundations of Western thought, contrasting the idealism of Plato with the empiricism of Aristotle. It delves into Socrates' Socratic method, emphasizing the importance of questioning to gain knowledge. The video outlines Plato's belief in a universe governed by perfect geometric forms and Aristotle's more practical approach based on observation and the natural world. It also touches on Aristotle's influence on Alexander the Great and his contributions to biology and the classification of living things, highlighting the historical significance of these philosophical giants in shaping scientific thought.

Takeaways

• 🤔 The video script explores the philosophical and scientific approaches of Platonism and Aristotelianism, contrasting idealism with empiricism.
• 👴 Socrates, despite not having a natural philosophy, influenced philosophy through his Socratic method, which emphasizes questioning to understand complex problems.
• 🏛️ Plato founded the Academy and emphasized idealism, believing in perfect abstractions and geometric laws that the real world only imperfectly exemplifies.
• 🌐 Plato's view of the cosmos was that of a perfect order, with elements made of perfect geometric solids and celestial bodies moving in uniform circular motions.
• 📚 Aristotle, a student of Plato, took a more empirical approach, observing the world to develop theories, which is a cornerstone of modern scientific practice.
• 🌳 Aristotle's cosmology included the four elements and a fifth, æther, and explained natural phenomena based on the elements' natural states and movements.
• 🔍 Aristotle was a meticulous observer of nature, making detailed observations of living things, which contributed to the field of biology and taxonomy.
• 🧠 Aristotle's theory of souls classified living things based on the complexity of their souls, with humans possessing a rational soul capable of thought and reflection.
• 🌏 The script discusses the social implications of science, noting that Aristotle's teachings influenced Alexander the Great, highlighting the historical interplay between science and power.
• 📖 Both Plato and Aristotle were prolific writers, with their works significantly influencing European thought for centuries, despite some of their ideas being disproven by later scientific advancements.

Q & A

Who is considered the inventor of science in Europe according to the script?

The Presocratics are considered the inventors of science in Europe.

What was Socrates' approach to knowledge and how did it influence philosophy?

Socrates believed that knowledge comes from asking questions and he developed the Socratic method, which involves asking questions to break down problems and test hypotheses.

What was the main difference between Plato's and Aristotle's philosophical approaches?

Plato was an idealist who believed in perfect abstractions and fit observations to his theories, while Aristotle was an empiricist who based his theories on observations of the world.

What was the significance of the Academy founded by Plato?

The Academy was significant because it was a place for philosophical learning, emphasizing proper thinking, and it was the first institution of higher learning in the Western world.

How did Plato's views on the nature of the universe influence his cosmology?

Plato's cosmology was based on the belief in perfect geometric shapes and uniform circular motion, which led him to propose that the cosmos was composed of perfect 'platonic solids' representing elements.

What was Aristotle's view on the elements and their natural states in the cosmos?

Aristotle believed that elements like earth, water, air, and fire, along with aether, had natural states and were always trying to return to their natural places, with earth at the center of the cosmos.

How did Aristotle's observations of living things contribute to the field of biology?

Aristotle's detailed observations of living things, such as the octopus's ability to change color, led to the creation of taxonomy and the classification of organisms based on a system of souls.

What was Aristotle's theory regarding the classification of living beings based on the concept of souls?

Aristotle's theory classified living beings based on the types of souls they possessed: plants had a vegetative soul, animals had a sensitive soul, and humans had a rational soul in addition to the other two.

How did Aristotle's ideas influence the concept of the Great Chain of Being?

Aristotle's classification system, which placed humans at the top of a hierarchy based on the complexity of their souls, contributed to the concept of the Great Chain of Being, which positioned all creatures on a ladder of perfection.

What was the Lyceum, and how did it differ from Plato's Academy?

The Lyceum was Aristotle's school, which was different from the Academy in that it was located in a grove of trees and had a more informal, walking-and-talking approach to learning, as opposed to the structured environment of the Academy.

Outlines

00:00

🎓 Socratic Influence and Philosophical Schools

The script begins with a quiz to determine whether one is a Platonist or an Aristotelian, setting the stage for a discussion on philosophical approaches. It introduces Socrates, who, despite not having a natural philosophy, influenced the teaching methods of philosophers through his Socratic method of questioning. This method, which involves breaking down problems and eliminating false hypotheses, is contrasted with empirical observation. Socrates' legacy is further explored through his students, Plato and Aristotle, who took his methods but reached different conclusions. Plato founded the Academy, emphasizing thinking like Socrates and basing his philosophy on geometrical laws, leading to an idealistic view of the universe. Aristotle, on the other hand, focused on empirical evidence and developed a more practical philosophy, observed through his time at Plato's Academy and later at his own Lyceum.

05:02

🌌 Platonic and Aristotelian Cosmologies

The second paragraph delves into the cosmological views of Plato and Aristotle. Plato envisioned a perfect cosmos with geometrically perfect atoms forming the elements, each with a corresponding platonic solid. His theory of the heavens posited uniform circular motion for celestial bodies, which was challenged by observations of retrograde motion. Aristotle, building on Plato's system, introduced a more complex cosmology that included the four elements and a fifth, æther, to explain the cosmos. He used physical sensations to categorize and explain the natural states and movements of elements, proposing that elements strive to return to their natural places, thus explaining phenomena like fire rising and rain falling. Aristotle's system was more aligned with observable reality and laid the groundwork for future scientific thought.

10:03

🐙 Aristotle's Classification of Life and Legacy

The final paragraph discusses Aristotle's detailed observations of living things, which led to the development of taxonomy and the concept of a 'Great Chain of Being.' Aristotle's classification system was based on a hierarchy of souls, with plants having a vegetative soul, animals having both vegetative and sensitive souls, and humans possessing all three, including a rational soul. His ideas about the soul and the classification of life were influential but also problematic, as they supported notions of scientific racism. Despite some controversial aspects, Aristotle's work provided a comprehensive framework for understanding life and the natural world, and his writings have been preserved and studied for centuries, significantly influencing Western thought.

Keywords

💡Platonist

A Platonist is someone who adheres to the philosophical views of Plato, an ancient Greek philosopher. Platonists believe in the existence of abstract, non-material forms or ideas that are the true reality, and that the physical world is a mere reflection of these perfect forms. In the video, Plato's idealism is contrasted with Aristotle's empirical approach, highlighting Plato's focus on geometrical laws and perfect abstractions as the basis for understanding the natural world.

💡Aristotelian

An Aristotelian refers to a follower of Aristotle, another prominent ancient Greek philosopher. Aristotelians emphasize empirical evidence and observation as the foundation for knowledge. The video describes Aristotle's approach as more common-sense and practical compared to Plato's idealism, with Aristotle observing the world and then developing theories to explain it, which aligns with modern scientific practices.

💡Socratic Method

The Socratic Method is a form of inquiry and discussion between individuals, based on asking and answering questions to stimulate critical thinking and to clarify ideas. Named after Socrates, this method is exemplified in the video through his approach to teaching, where he constantly asks questions to help students break down problems and test hypotheses, even embracing the elimination of wrong ideas as a step towards truth.

💡Idealism

Idealism is a philosophical belief that reality is mentally constructed or immaterial, with the real being the ideas or forms rather than the physical objects we perceive. In the context of the video, Plato's idealism is showcased through his belief in perfect geometric forms as the true reality, with the physical world being an imperfect copy of these forms.

💡Empiricism

Empiricism is a philosophical stance that asserts that knowledge arises from experience and evidence, particularly from the senses. The video contrasts this with idealism, highlighting Aristotle's empirical approach to understanding the world through observation and evidence, which is a cornerstone of the scientific method.

💡Presocratics

The Presocratics were early Greek philosophers who preceded Socrates and made significant contributions to the development of science and philosophy. The video mentions them as inventors of science in Europe, but notes that they are often overshadowed by the more famous Socratic philosophers.

💡Academy

The Academy, founded by Plato, was an institution dedicated to philosophical learning and the pursuit of knowledge. The video discusses how Plato emphasized proper thinking and even had a dictum over the door stating that only those knowledgeable in geometry should enter, reflecting the importance of logical and abstract thought in his educational philosophy.

💡Lyceum

The Lyceum was a school founded by Aristotle in Athens, known for its informal setting and focus on walking and discussing philosophical and scientific ideas. The video contrasts the Lyceum with Plato's Academy, highlighting Aristotle's preference for a more practical and observational approach to learning.

💡Taxonomy

Taxonomy is the scientific classification of organisms into groups based on shared characteristics. The video credits Aristotle with attempting to classify the world in an orderly system, which laid the groundwork for modern taxonomy. His observations of living things and his creation of a system based on a hierarchy of souls were part of his broader effort to understand and categorize life.

💡Great Chain of Being

The Great Chain of Being is a concept that suggests a hierarchical order to all existence, from the simplest to the most complex or 'perfect' forms. The video mentions how Aristotle's ideas influenced this concept, which positioned humans, particularly males, at the top of this hierarchy. This idea has been criticized for its potential to support scientific racism and other forms of discrimination.

Highlights

Socrates introduced the Socratic method, emphasizing the importance of questioning to gain knowledge.

Plato founded the Academy, focusing on philosophical learning and the pursuit of knowledge through dialogue.

Plato's philosophy was based on geometrical laws and idealism, with a belief in perfect abstractions.

Aristotle's approach was more empirical, observing the world to draw conclusions, which is foundational to modern scientific practice.

Aristotle was a prolific author, and his works on natural philosophy, including 'Physics', have had a lasting impact.

Aristotle's cosmology included the concept of elements striving to return to their natural states, explaining phenomena like fire rising.

Plato's theory of the cosmos was based on perfect geometric shapes, such as platonic solids representing elements.

Aristotle's Lyceum was an informal school set in a grove of trees, reflecting his love for nature and walking.

Aristotle's observations of living things, like the octopus's color-changing ability, were detailed and methodical.

Aristotle's taxonomy system was based on a hierarchy of souls, from plants with vegetative souls to humans with rational souls.

Aristotle's classification system influenced the Great Chain of Being concept, which排序了生物的完美程度直到达尔文时代。

Aristotle's ideas on the movement of elements, such as why rain falls and flames rise, were based on common sense and observation.

Plato's and Aristotle's differing views on the cosmos and natural philosophy shaped European thought for centuries.

Aristotle's influence on Alexander the Great highlights the social aspect of science and its service to political powers.

The Socratic method's emphasis on questioning and negative hypothesis elimination is a precursor to scientific inquiry.

Aristotle's works were preserved by Arabian scholars, contributing to the continuity of scientific thought.

Transcripts

Pop quiz: are you a Platonist or an Aristotelian?

An idealist or an empiricist?

Do you think up neat rules to describe the universe and then try to fit data into your theory?

Or do you observe the world and draw conclusions from what you see?

Do you trust math, or your senses?

Before you decide, let’s take a trip to urban Athens circa 399 BCE…

[Intro Music]

Last week, we met the Presocratics: despite

having by any reasonable standard invented science in Europe, these thinkers are lumped

together today as simply “not Socrates.”

So who was this smarty pants?

Socrates didn’t have a single, clearly formulated natural philosophy.

He didn’t even study nature!

He studied politics and morality and prided himself on not claiming to know things.

But Socrates did two important things: he asked a lot of questions, which influenced

how philosophers went about teaching their ideas.

And he inspired the two rockstars of classical Greek philosophy.

Socrates held that knowledge comes from asking questions.

So many questions!

His name is attached to the Socratic method—in which you constantly ask questions so that

students can steadily break down a big problem into smaller parts, parts they can test hypotheses against.

It’s okay if they realize that a hypothesis is wrong: in fact, it’s good!

It means they’re moving away from falsehood.

The Socratic method is an example of negative hypothesis elimination, or proving that something

is wrong to narrow down the possibilities of what might be right.

But Socrates’s biggest legacy might be his student, Plato, and his student’s student,

Aristotle.

Both were inspired by Socrates’s methods, but they arrived at some very different conclusions

about the world.

We know a lot about Socrates thanks to his

students.

Chiefly Plato founded a physical school called the Academy to train Athenians in how to think

like Socrates.

Plato wrote down dialogues between Socrates and other thinkers including Parmenides: he

was the Eleatic philosopher who believed that nothing really changes, and thus we can’t

trust our senses.

This had a big impact on Plato.

Whose best known works include Republic, in which Socrates defines justice and argues

for rule by philosopher-king instead of democracy, and Timaeus, in which Socrates talks

about the nature of the universe.

Plato had a big impact on thinking about thinking.

Today, we still use Plato’s name for a place of philosophical learning, “Academy,”

to describe the concept of higher education in general.

At the original Academy, Plato emphasized training in how to think properly.

Over the door of the Academy was inscribed the dictum, “Let no one enter here who is

ignorant of geometry.”

Plato based his own philosophy on geometrical laws.

He taught a Pythagoras-inspired idealism, or a theory of nature based on perfect abstractions—rules,

of which real-world stuff could only ever be imperfect examples.

So Plato had to fit his observations to his theory.

That idealism is one of the reasons people think of Plato as more of a philosopher than

a scientist.

Plato built on the work of the Presocratic schools.

But he developed a more complete way of looking at the natural world than they did.

And his students took off in search of solutions, even as they changed his underlying theory.

The only Greek who wrote more philosophy than Plato was Plato’s own star student and rival,

Aristotle.

Compared to Plato’s idealistic abstractions,

Aristotle’s philosophy makes more common sense.

His ideas are based on empirical evidence: he observed the world and then came up with

a theory that explained it.

This order of operations is at the heart of modern scientific practices.

Aristotle was from Macedonia, in the north of Greece.

But he studied at Plato’s Academy in Athens for twenty years, until Plato died.

Afterward, Aristotle took a lucrative gig: King Philip II of Macedonia hired him as tutor

to his son, Alexander.

And, you know this particular Alexander: he decided to conquer the entire earth.

Before age thirty, he ruthlessly conquered much of Asia, Africa, and Europe, ruling over

more area than anybody until Genghis Khan.

Aristotle’s influence on Alexander “the Great” reminds us that science is

always social.

From the very beginning, scientists have served bad, heartless dudes.

Aristotle, a man who literally wrote the book Ethics, pushed his most famous pupil to invade

Persia, kill “barbarians,” and become a brutal warlord.

After Alexander died young, Aristotle went back to Athens to start his own school, the

Lyceum.

The Lyceum was pretty different from Plato’s Academy.

Because Aristotle liked plants and liked to walk and talk, his school wasn’t in a building,

but a grove of trees outside the city.

And his school was called the Peripatetic, meaning “walkie” and thus informal—not

like the Academy.

It was during the Lyceum years that Aristotle probably wrote many of his most famous works,

including Metaphysics, On the Heavens, On the Soul—which is actually an amazing book

of proto-biology-meets-psychology—and his school’s highly influential set of textbooks

on natural philosophy, called Physics.

How did Aristotle answer our big questions

about physics, such as “what was stuff?”

And “where are we?”

He posited a complete system, joining the elements and the heavens.

This became the basis for European thought about the physical world for two thousand years!

Let’s compare Aristotle’s system to his mentor Plato’s in this week’s ThoughtBubble.

For Plato, the cosmos was perfect.

It had perfect rules that could be studied.

And all cosmic stuff was made up of atoms that were perfect geometric “platonic solids”,

each creating one element: tetrahedrons of fire, cubes of earth, octahedrons of air,

icosahedrons of water, and dodecahedrons as the shape of the whole universe…

Like a giant celestial set of D&D dice!

Plato’s theory of the heavens stated that the wandering stars—that is, the planets—followed

a path of uniform circular motion.

You see,

the wandering stars must move in perfect circles, since the cosmos is orderly.

Ah, but this one is moving backwards!

Plato’s students could see that Mars, for one, seemed to jump backwards, showing retrograde

motion.

Plato didn’t really have an explanation.

European astronomers would spend the next two thousand years meticulously trying to

solve this problem.

They’d end up learning a lot in the process.

How did Aristotle build on Plato’s system? Aristotle’s cosmology was abstract, too,

but attempted to make sense of observations about the world.

He crossed those same four elements, plus a new anti-void one called æther, with four

physical sensations: hot and cold, dry and wet, and used these to explain everything:

Earth was the heaviest element, so it was the center of the cosmos.

Water was lighter than earth so the oceans rested on top of the earth.

So far so good.

Air’s natural state is above water.

That also checks out!

Fire sat on top of air, which is a little weird… but it does go up, I guess?

And way out beyond these four terrestrial spheres—out past the Moon—spun the stars,

acting according to their nature as ætherial, or perfect-circle-moving, objects.

And nowhere, anywhere in this theory, was a void.

Nature abhors a vacuum!

In Aristotle’s cosmos, all of the elements were actively trying to get back to their

natural states.

Why did flames rise?

They were just trying to get back to the fiery celestial realm above the air.

Thanks Thought Bubble.

From the Presocratics to Plato to Aristotle, we’ve ended up with a bunch of spheres inside

of spheres, each with a natural tendency.

This confirmed the average Bronze Age farmer’s experience… and ours.

The earth seems to stand still.

Water sits on earth.

Air isn’t very heavy.

Aristotle recognized that elements didn’t always exist in their pure forms.

A tree, for example, was a combination of earth, water, and air: roots go down into

the earth, and branches up into the air.

His theory also worked for comparisons.

Why does a book fall faster than a piece of paper?

Because it has more earth in it.

Aristotle could even explain natural phenomenon.

Why does rain fall from the sky to the ground?

Why do volcanoes shoot fire up?

Obviously this isn’t how I think gravity works, but it’s a way of explaining it that

made sense to the Ancient Greeks.

Where Plato saw a world of ideal shapes, Aristotle had a theory that acknowledged that we’re

all kind of a hot mess.

Things are naturally jumbled up, but always trying to get back to their essential place.

[Living things] Aristotle also loved looking at living things.

And he looked closely.

He noticed, for example, that the octopus can change color—which is awesome—and

that male octopi have a special arm called a “hectocotylus”—which is… something

you should Google.

Because it’s weird and gross but also kind of awesome.

And it wasn’t confirmed by scientists until the 1800s!

Aristotle thus trusted that knowledge proceeded from the experience of the senses.

In works such as History of Animals, among others, he wrote down observations like these

about all kinds of organisms.

He also tried to classify the world in an orderly system, giving rise to taxonomy.

When he attempted to answer the question “what is life,” the taxonomy he created relied

on a system of souls.

Plants have a vegetative soul, responsible for reproduction and growth.

Animals have a vegetative and a sensitive or animal soul, responsible for mobility and

sensation.

And humans—and only humans—have a vegetative, a sensitive, and a rational soul, capable

of thought and reflection.

This led Aristotle to further theorize that all things can be placed on a line from simplest-slash-least-soulful

to highest-slash-most-soulful.

On one end, he placed plants, then worms, and so on.

These low animals bore their offspring cold, dry, and in thick eggs.

The higher animals made warm and wet babies.

So of course, at the other end of the line, Aristotle placed men.

Meaning not “humans,” but dudes: according to him, cold maternal blood produced inferior

humans, AKA girls, while hot paternal semen produced boys.

Aristotle was… maybe not someone we’d want to elect as our philosopher-king today?

But Aristotle’s system of classification again seemed to confirm his classical and

medieval readers’ daily experiences.

His proto-biological ideas stuck around in various forms until Darwin, getting lumped

under the heading of the Great Chain of Being—that all creatures on earth stand somewhere on

a ladder of perfection up toward God.

You may have already guessed that this concept has been particularly troublesome when it

comes to scientific racism.

But that’s a story for later.

The creepier effects of some his ideas aside,

Aristotle had an answer for everything.

For the most part, these were based in observation and conformed to common sense.

His answers were able to explain how the world worked…

most of the time.

And not only did Aristotle come up with a complete theory of everything, he wrote it

down.

He was a prolific author, and a significant percentage of his texts have survived thanks

to our Arabian scholars.

Then again, Plato’s transcendental ideas about the cosmos—even if wrong in their

particulars—inspired centuries of scholars to think about the universe as having underlying

laws, ones that hold regardless of what our senses can show us.

So are you a Platonist or an Aristotelian?

Or, taking a page from Socrates, is that a trick question!?

Next time—we’ll follow Alexander the Maybe-Not-So-Great to India to witness the rise of the Maurya

dynasty, set the earth spinning on its axis, and found a science of life!

Crash Course History of Science is filmed in the Dr. Cheryl C. Kinney studio in Missoula,

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