Although I often sound opinionated in daily conversations, I haven’t actually read many serious books. My knowledge of philosophy is, frankly, at the level of an illiterate. Over the past six months, I’ve participated in quite a few reading groups and worked through some philosophy books. To my surprise, many of the ideas matched thoughts I’d had on my own through random speculation. I suddenly felt a bit tricked—maybe all those pretentious types who make philosophy sound impenetrable had been fooling me. If a philosophy book is translated in a way that makes it unreadable, that means it’s mistranslated. Someone said this recently, and I couldn’t agree more. This is what philosophy—or thought itself—is really about.
I feel it’s time to systematically learn the history of thought. Experiencing two thousand years of human wisdom—the journey won’t be boring. If it is, that just means you’ve opened it the wrong way.
My friend Tifeng recommended Gunnar Skirbekk’s A History of Western Thought. Let’s follow the author on this journey through the history of ideas and enjoy the pleasures of thinking.
This will be a casual series—written as I read, with no fixed length or schedule. Notes from a philosophy beginner, meant for newcomers like me to actually understand.
The First Question:
What is the true nature of the universe and everything in it? Is there something common that underlies all the countless things we see? Amidst all change and transformation, is there anything that remains unchanged?
The First Generation of Philosophers
Let’s clear our minds for a moment and think back to childhood—we’ve probably all asked similar questions. If the history of human thought were the story of one person growing up, then Thaleswould be the first to open his eyes to nature.
Thales declared: “All things are water.”
Perhaps he had seen water turn into vapor, or freeze into ice; perhaps he noticed how every plant and animal was full of water. Rivers, lakes, and seas were water in plain sight—so could everything else, in the end, simply be water in different forms? This conclusion may sound absurd today, yet its meaning is extraordinary. By saying all things are water—not the work of gods—Thales announced that the world is knowable, that reason, not myth, could explain the universe. Starting with him, human thought progressed from mythical thinking to rational thinking, beginning the journey of conquering the universe through reason.
Next, someone challenged him, saying that if everything is water, then anything could become anything else. For instance, earth could turn into water, water could turn into a person—which means earth could turn into a person, and vice versa. So why not say everything is earth, or everything is human, instead of insisting everything is water? This person argued that the unchanging element must be something indeterminate.
Another wondered: if everything is water, how does water become everything else? He claimed that all things are air—air cools into water, which freezes into ice, and when heated, air turns into fire. From this idea came the famous theory of the four elements: fire, air, water, and earth.
The Second Generation of Philosophers
The first generation asked: What is the unchanging element behind everything? The second asked a deeper question: * Does change even exist?*
One side said: everything flows, nothing stays the same. The other said: change itself is impossible—it cannot even be thought.
Heraclituswas the champion of change. He is remembered for saying: **“No one ever steps into the same river twice.”**He believed that all things are in flux, and what does not change is the law of the unity of opposites. Take ourselves, for instance. We may appear unchanged, but within us, the body is always aging. Life and death are locked in balance—for now, life holds the upper hand; someday, death will. What seems unchanging is merely a temporary harmony between two opposing forces.
The one who denied change was Parmenides. He argued that only * what exists* can be known, and * what does not exist* cannot be conceived. To say that something “changes” is to say that what once existed has vanished and something new has appeared from nothing. But * nothing* cannot be thought—it has no place in reason. Thus, within thought itself, **change is impossible.**All being is one, indivisible, and unchanging. The illusion of change, he said, is merely the trickery of our senses. As absurd as this may sound, I think Parmenides was, in a way, anticipating the modern idea of the conservation of matter. When you see a leaf turn yellow, you think it has changed—but in truth, the substances that make up green and yellow are still all there, unchanged in quantity.
The Third Generation of Philosophers
Faced with all these contradictory yet individually reasonable claims, the third generation tried to split the difference.
The representative figure is Empedocleswith his theory of composition: 1.
The world is composed of four basic elements: fire, air, water, and earth (this came from the debates of Thales’s generation) 1.
Besides the elements, there are two forces: “Love” which unifies, and “Strife” which divides (here we can see Heraclitus’s influence) 1.
The four elements cannot change in quality or quantity. Different quantities of the four elements combine to create all things (here we can see Parmenides’s shadow)
Building on previous thinkers, Empedocles constructed a world model that includes both change and constancy: the unchanging part is the quantity and properties of the four elements; the changing part is how they combine and separate.
Against this backdrop, Democritus’sbrilliant invention—atomic theory—burst onto the scene. Empedocles basically stitched earlier theories together; Democritus broke new ground in almost every direction.
He believed the world is composed of atoms making mechanical movements in empty space: 1.
On the composition of matter: Instead of tangible things like fire, air, water, and earth, he creatively proposed that everything is made of indivisible tiny particles 1.
On the question of existence: While Parmenides believed the void (non-existence) lay beyond human thought, Democritus argued that void is the precondition for existence 1.
On how change occurs: He believed all change is determined entirely by atoms colliding with each other, like playing marbles—governed only by mechanical forces. He rejected the mystical forces like love, hate, or spirit that other philosophers favored.
This was the 4th century BCE—two thousand years before modern physics and chemistry. Without any experimental apparatus, the Greeks developed this remarkably advanced model through nothing but observation and rational thought. It’s staggering.
But like many brilliant theories, Democritus’s atomism was too far ahead of its time. Asking people to believe in invisible particles was a tall order for ancient audiences. And the theory was too mechanical—it struggled to explain living phenomena.
So what ended up dominating Western thought for the next two millennia was Aristotle’s natural philosophy. On material composition, Aristotle took Empedocles’s four elements and added a fifth—”aether”—which makes up the heavenly bodies. On motion and change, he proposed his doctrine of four causes: change is guided by purpose (final cause), requires external force (efficient cause), depends on the underlying material (material cause), and corresponds to the final form (formal cause). Take making a cup: my intention to create a cup is the final cause; my hands shaping the material is the efficient cause; whether it ends up a transparent glass or sturdy metal cup depends on what I use (material cause); and the finished cup holds water because I gave it the form of a cup (formal cause). These four causes together determine how things change.
Finally, I have to mention the Pythagorean school, whose answer differs from everyone else’s.
Pythagoreans believed the unchanging element is mathematics. Pythagoras proved the Pythagorean theorem—showing math could be applied to surveying land (geometry) and other physical reality. He discovered the golden ratio in musical harmonies—revealing deep correspondences between mathematics and music. Even celestial motion follows mathematical laws. Physical things perish, but mathematical truths don’t. And mathematical knowledge is certain—proven by logic. So they believed mathematics is the unchanging principle underlying nature.
So much for the cosmological questions that first preoccupied philosophy. Next time we’ll see what brilliant ideas the Greeks had about knowledge, ethics, and politics.