Science’ has become a blanket term, devoid almost entirely of meaning. We often throw it around, in large part unconsciously, when we wish to put some authority behind a claim. I see advertisements claim that their goods or services are backed by science. Internet blogs, health and diet forums, self-improvement books, and this-that-and-the-other-thing each claim to stand on the authority of ‘science’.

But, what’d ya’ll mean by ‘science’? What is its nature or quality? And what, if anything, gives it authority? Many of us, when pressed to explain it, quickly find the entire foundation which we believed it to have been standing on to collapse.

Let’s take a closer look, then, to see if we can’t sharpen up our understanding of ‘science’. And hopefully make ourselves more resilient against those empty claims disguised as ‘science’.

The Rebirth of the Ionian Tradition

Science is often associated with the scientific revolution — a period near the turn of the seventeenth century marked by a rebellion against the dogmas of the Catholic Church and accompanied by a hunger for the individual’s free pursuit of knowledge. But what was the catalyst of this rebellion and appetite for new knowledge, especially after a thousand years of faithful adherence to the Bible and the Catholic Church?

The catalyst was books — Ancient Greek writings, to be specific. You see, this actually wasn’t the first scientific revolution. Science, in its most general form, was actually created some two thousand years earlier by a small group of Greek renegades in the Ionian colonies.

After several cultures clashed near the Mediterranean, these Greeks realized that we actually don’t know much about our home the cosmos. After all, each civilization had invented their own gods — gods in their own image — as well as their own story about the world and our place in it. With so many gods and stories, then, each conflicting with the others, these Greeks concluded that we humans must be fallible — that our explanations of the world are mere guesswork.

Rather than throw their hands in the air and abandon their search for truth, however, they invented the single most important tradition necessary for the growth of human knowledge — a tradition of reason; a tradition of an open and honest critical discussion where the aim is to move nearer to truth. You can see this spelled out quite clearly by the Greek philosopher Xenophanes (c. 570 – c. 475 BC):

The gods did not reveal, from the beginning,

All things to us; but in the course of time,

Through seeking we may learn, and know things better…

These things we learn are like truth.

But as for certain truth, no man has known it,

Nor will he know it; neither of the gods,

Nor yet of all the things of which I speak.

And even if by chance he were to utter

The final truth, he would himself not know it:

For all is but a woven web of guesses.

The birth and development of the Ionian tradition is a marvelous story. It has given us so much that we have come to appreciate. It has allowed even the lower classes to live more comfortably than kings of old. And, if this doesn’t fill you with tremendous gratitude, consider that it has been invented only once.

It began with Thales and Anaximander and lasted only a few hundred years before it started to take a series of blows, first with the Persian empire’s invasion of northern Greece. And, again, when the Greeks exchanged their words for swords under the Macedonian and Roman empires. It was finally pushed to near extinction when the Catholic Church, largely under the spell of Plato and Aristotle, suppressed all free thought and claimed that the Bible was the only true source of knowledge. And, though it was picked up briefly at the start of the first millennia by the Abbasid caliphate, it didn’t make a stable recovery until after the fall of Constantinople in 1453, when scholars migrated to Italy, bringing with them what ancient writings had survived.

The Copernican Revolution

When people finally rediscovered Ancient Greek philosophers like Protagoras, an optimism caught flame in Italy, which quickly spread to the rest of Europe. Reason had once again fertilized the growth of art, poetry, and thought, as it once did in Ancient Greece. People like Michelangelo, Shakespeare, and Leonardo Da Vinci seemed to have woken up every day like kids on Christmas, ecstatic to see what the Space of Possibility had in store for them next.

In cosmology, however, the rebirth of ancient Greek philosophy stirred up quite the conflict.

You see, most people throughout history believed the earth sits at the center of the cosmos. And, of course they did. Just look for yourself — everything seems to rotate around us. Plus, I don’t feel the earth moving. Do you? In any case, this wasn’t an open question for Christians. The Bible is clear: the sun stopped its rotation around the earth and stood still over Gibeon. (Joshua 10:12). So, there wasn’t much room for debate on the matter — the holy scriptures said so and that was that.

Enter Nicolaus Copernicus (1473–1543), an ecclesiastic astronomer who was about to fuck up the game. Copernicus thought holy scripture had it all wrong — it’s not the earth, he argued, but the sun that sits at the center of the cosmos. Why? No, not because of some cool new observation.

Copernicus’ great ‘insight’ was actually inspired by Plato’s writings. Plato tells us that the sun, because it gives us light, is of the highest order in the material realm (which he contrasted to the immaterial realm of forms). ‘By god, Plato’s right,’ Copernicus thought. ‘Because the sun is the most important thing in the material realm, it must have divine status at the center of the universe.’

All the hype and legacy for that so-called ‘insight’?! Yeah, I know. But, the consequences of this ‘insight’ are hard to exaggerate.

Because Copernicus knew it would piss-off his lovely employer, the Catholic Church, he left his heliocentric theory to a friend to publish after his death. And I don’t blame him. The priests back then weren’t like the goofy old child-molesters you see today. No no no, fuck with these guys, and you were done.

And it wasn’t just them Copernicus had to worry about. The reformers wouldn’t take his heliocentric shit either. Years after its publication, Martin Luther said, “People give ear to an upstart astrologer who strove to show that the earth revolves, not the heavens…sun and the moon…. This fool wishes to reverse the entire science of astronomy; but sacred Scripture tells us that Joshua commanded the sun to stand still, and not the earth.”

In any case, a few years after its publication, leaders of the Catholic Church met up in the Italian city of Trent to figure out how to curb the German princes and reformers like Luther who had started to fuck with the Vatican’s authority. The Council of Trent then issued decrees covering every aspect of Church authority. It published the Index of Forbidden Books, which named 583 heretical texts, including Copernicus’s On the Revolutions of the Celestial Spheres. It formed a band of militant missionaries called the Jesuits. And it reestablished the Roman Inquisition to torture heretics until they restored their faith.

There was one man, however, who wouldn’t take their shit. Giordano Bruno (1548–1600) is arguably one of history’s bravest defenders of free-thought. That little rebel dared to read the books that had been banned by the Church. And, in one of these books, Bruno stumbled across a thought experiment by the ancient philosopher Lucretius, who asked his readers to imagine standing at the edge of the universe and shooting an arrow outward. If the arrow keeps going, space must be infinite, he argued. If, on the other hand, the arrow hits a wall, then that wall must lie beyond what you thought was the edge. Now, if you stand on that wall and shoot another arrow, the same two possibilities remain. Either way, it seemed to Lucretius as if the universe was infinite.

Shaky logic, no doubt. But, in any case, Bruno ran with this idea. Still a deeply religious man, like everyone else at the time, Bruno thought that his god must be infinite. So, why should the cosmos be anything less? His new picture of the cosmos, then, was a world where there was no up, no down, no edge, and no center. The stars, he believed, are just distant suns surrounded by planets of their own. And some of these planets may even foster life of their own.

Stoked about his insight, Bruno set out to share his new worldview. But, of course, the Inquisition wasn’t gonna sit by and watch. They arrested Bruno and put him on trial for heresy. Bruno admitted minor theological errors and instead tried to emphasize the philosophical character of his belief. But the inquisitors didn’t bite. They pointed their fingers at him and demanded that he confess his sins or burn.

Bruno bravely said he had nothing to confess.

After they read him his death sentence, Bruno looked those twats square in the face and said, ‘Perhaps your fear in passing judgment on me is greater than mine in receiving it.’ And on that cold February morning in the year 1600, the Inquisitors dragged Bruno through the streets with his tongue in a gag, tied him up, and burned him alive.

A mere ten years later, Galileo Galilei (1564–1642) made an astonishing new discovery with his fancy new telescope — four moons orbit around Jupiter! That meant the geocentric — or earth-centered — view was refuted; clearly not everything revolves around the earth! The savage Christian theologians, though, showed no humility. They weren’t about to go down without a fight. So, they ordered Galileo not to hold, teach, or defend heliocentric ideas.

But Galileo, the clever smartass that he was, decided to outwit them. He wrote a book and framed it as a hypothetical discussion among three friends about the validity of the heliocentric model. His con worked initially, though the Church required him to add a preface acknowledging that the Church’s objections to the heliocentric model were perfectly valid. So, Galileo added a brilliantly sarcastic preface: “Several years ago there was published in Rome a salutary edict which, in order to obviate the dangerous tendencies of our present age, imposed a seasonable silence upon the…opinion that the earth moves.”

The book was an immediate success. It wasn’t long, though, before the Church caught onto his sarcasm. Galileo played dumb, at first, and claimed that the Dialogue was clearly hypothetical, and that he was neither holding nor defending the heliocentric model. But the head of the Inquisition called bullshit and threatened Galileo with ‘greater rigor of procedure’ — aka, torture — if he wouldn’t confess his sins. So, like a good little deacon boy, Galileo bent over for an assembly of pious dicks and obediently confessed his sins.

With this confession in hand and largely thanks to Galileo’s popularity, he got a much better deal than Bruno. But still, Galileo was sentenced to house arrest for life and his book was added to the Index of Forbidden Books. Outside the reach of the Inquisition, however, his book spread like wild fire. And, just over a quarter-century after Galileo’s death, the geocentric model was abandoned.

The Ionian tradition was back in full swing.

The Scientific Revolution

Galileo’s observational refutation of the geocentric model of the universe was dope, for sure. But he didn’t stop there. Before Galileo, Aristotle had gone largely uncontested. In particular, nobody had rigorously tested his claim that the heavier an object is, the faster it will fall. Galileo, though, not one to take people at their word, decided to build a ramp, place two balls of different weight at the top, and let ’em go.

If Aristotle was right, the heavier ball should have rolled down the ramp faster than the smaller ball. But, as you know, that’s not the case. No matter the weight of the ball, each time Galileo rolled the balls down the ramp, they would move at exactly the same speed. In one fell swoop, then, Galileo not only refuted the great Aristotle — the man who for centuries was simply referred to as The Philosopher — but he also discovered a universal rate of acceleration, thereby clearing the way for Kepler, Newton, and Einstein to improve our understanding of gravity.[1]

Although Galileo was an incredible scientist, I believe it was Johannes Keppler who, among the early giants of the scientific revolution, best understood how knowledge is created. Inspired by his love for harmony in music, mathematics, and god, Kepler relentlessly searched for an explanation to describe the planets’ relations to the sun. But no matter how harmonic a hypothesis was, Kepler didn’t let his metaphysical belief in a divine harmony override observational refutations. Though Copernicus’ idea of circular orbits was certainly harmonic, Kepler humbly discarded the theory after it was refuted by Tycho Brahe’s observations.

Kepler, more than any of his contemporaries, understood that the only way to move nearer to truth is through the humble method of trial and error. He understood that when you’re faced with a problem, all you can do is guess. And, if you wanna know if your guess holds any truth, you gotta test it empirically. This he did over and over again. Many times in his writings, he says that he approached his search for truth by first formulating a hypothesis and then discarding it if it was refuted by observation. It took Kepler dozens of failed attempts before he finally created the elliptical theory of the orbits.

Though it was Kepler who seemed to have best understood how knowledge is created, it was actually his mistaken contemporaries Francis Bacon and René Descartes who received all the hype for their epistemologies — or theories of knowledge. But, before I throw shade all over their respective theories, let me first give ’em credit where credit’s due.

The scientific revolution was largely inspired by the optimistic belief that each person has the power to acquire knowledge for herself. And, no doubt, Bacon and Descartes were the biggest forces behind that optimism. They argued that you don’t need to look to religious authority for truth because you already have the ability to discern truth for yourself.

This had momentous effects. After all, for the previous millennium, Christian dogma had stripped people of their optimism because it had claimed that the Bible was the only true source of knowledge. It was perfect and in no need of improvement. There was therefore no need for progress. But, after Bacon and Descartes encouraged us to raise our middle fingers to the Church and reclaim knowledge for ourselves, our intellectual and moral progress went through the roof.

For this, I am extremely grateful. As for their epistemologies, however, well…let’s just say they started us off on the wrong foot. For each just replaced one dogma — the Bible — for another. In Bacon’s case, it was the senses; and in Descartes’, it was an infinite god who is the cause of all things.

Let’s start with Bacon.

Bacon believed nature is an open book that we can read with our senses. But, before we can read it, we gotta cleanse ourselves of all our indoctrinations, for they poison our senses and distort nature’s true reality. Only after we’ve sucked the poison from our senses, then, will our senses be able to reliably sketch facts onto our minds.

Bacon’s epistemology [3] was later developed and defended by many great thinkers, including John Locke, who said the mind is like a tabula rasa — or blank slate — which is filled by sensory experience. It now goes by the name Empiricism.

Despite what Bacon and Locke believed, and despite what many still believe, it’s impossible to read or infer knowledge from nature. After all, a blank slate can’t do anything. In order to collect data from the environment, you must already have a theory in place to do something with the data — the 1s and 0s. And, as you know with all the software available to us, there are many things you can do with 1s and 0s. These theories, then, are conjectural — they’re created for specific aims or to solve specific problems.

To demonstrate this point, the philosopher Karl Popper would ask his students on the first day of class simply to observe. And, after a long, awkward silence, a brave student would finally muster up the courage to say, ‘Um…Professor, what exactly do you want us to observe?’

‘Ah hah!’ Popper would reply, ‘Precisely the point. In order to observe, you must first have in mind a definite problem and hypothesis to guide your observation — to tell you what you seek and where to seek it.’ Charles Darwin also seemed to find this point obvious: ‘How odd it is,’ he states, ‘that anyone should not see that all observation must be for or against some view….’[2]

There’s no escape from it. Every observation is theory-laden. None of your sensory perceptions represent how the world actually is. You don’t, for example, experience the nerve signals traveling from your sensory receptors to your brain for what they really are — that is, electrochemical wave patterns. Nor do you experience them as being where they really are — that is, traveling through your neurons.

No, instead, you believe they’re out in the world somewhere. But yellow, say, doesn’t really exist ‘out there.’ Rather, your brain creates the experience of yellow through a computational process of electrochemical signals. When you perceive yellow, you’re really detecting a pattern of incoming electromagnetic waves that repeat themselves about 520 trillion times a second. And after they’re captured by a molecule in your eye, the signal is then relayed through a number of biological systems — again, theories — before yellow finally arises in consciousness. As with all knowledge, your conscious experience of the world is but a web of guesses. So much for Bacon’s epistemology.

Okay, let’s see how Descartes’ theory fairs.

Knowledge, Descartes believed, requires a conviction ‘so strong that it can never be shaken.’[3] To begin our search for knowledge, then, we must, like a home-builder, first clear the land of all sand and mud so we can lay our foundation on solid ground. That is, we must begin by throwing away every belief that is even the slightest bit doubtful.[4]

This, he argues, includes the senses, since they are always deceitful. Just look for yourself, he tells us. An object at a distance appears to be quite small. But its size doesn’t really change as you move towards or away from it. Nor can I, he argues, assume the object is actually there, even if I assume that my perception of it is distorted, since I may be dreaming. And, because there’s no way to distinguish between waking and sleeping life, the senses are entirely untrustworthy.[5]

Well shit, he thought. Where, then, can we lay our foundation? Hold up…I think I got something here: What about the fact that I’m thinking? No matter whether I’m dreaming or awake, I am still thinking. I can therefore be certain that Iexist.

Perhaps it would have been better to say, ‘There is thinking, therefore there is thinking” — a tautology like Parmenides’ famous tautology ‘What is, is’ or ‘What exists, exists’. In any case, whatever the merits to this claim, it seemed to offer Descartes the foundation he was looking for.

From here, then, his next challenge was to deduce knowledge of something else — namely, god. His argument runs as follows:

(1) In order for a thought to contain truth, there must be at least as much reality in the cause of that thought as is contained in the thought — in other words, a thought can’t come from nothing.

(2) And, since I am only finite, the thought of an infinite god couldn’t have possibly come from me.

(3) All my thoughts, therefore, must have come from an infinite god.

In Descartes’ own words: ‘If I did not possess knowledge of God, I should never have true and certain knowledge about anything….’[6]

Well, there you have it. Though Descartes attacked dogma as a legitimate source of knowledge, in the end, he rested his entire epistemology on another dogma — an infinite god who is the cause of all things.

So much for Descartes’ theory of knowledge.


What’d ya’ll mean by ‘science’? I don’t know. But, when I think of science, I think of that wonderful and fragile bit of knowledge that was created some twenty-five hundred years ago in the Ionian colonies, where a group of Greek renegades, in recognizing their fallibility, figured the only way to move nearer to truth was to propose bold solutions to genuine problems, and then chip away at their mistakes through open, honest, and rigorous criticism.

Also, as a part of that criticism in science, I think of that important element of empirical refutability, which Galileo and Kepler deployed so well. As Kepler noted, if you want to know whether a claim holds any truth, then you need to test it empirically. This implies that a scientific claim must stick its neck out — it must leave itself vulnerable to refutation. And, the further it sticks its neck out, the better or more powerful the claim.

Falsifiability is a modern requirement for scientific claims. It was expressed succinctly in the twentieth-century by Popperto distinguish metaphysical claims from the empirically rigorous claims of science. (For more information about falsifiability, see Popper’s Problem of Demarcation.)

Finally, it is critical to keep in mind that there is no source of knowledge. All human knowledge — scientific claims or otherwise — is conjectured. This was the crucial missing piece for Bacon and Descartes, whose biggest mistake was, perhaps, how they framed their initial problem. Because each asked where knowledge comes from, both went looking for its true source. It’s hard to blame ’em, though. After all, for the last thousand years, the entire Western world thought the Bible was the only true source of knowledge. So, it would have been completely natural to think, ‘If the Bible isn’t the true source of knowledge, then what is?’

The switch, however, from the Ionian’s conjectural-based knowledge to this source-based knowledge didn’t begin with the Church. As you’ll see in the next episode, it began hundreds of years earlier with Aristotle’s theory of epistēmē — or demonstrable knowledge. For Aristotle, the true source of knowledge was a mixed bag of induction and logic — the repetition of experience to acquire perfect knowledge of concepts, which we can then use to deduce the ultimate explanation of the world, an explanation that is eternally infallible.

In the next episode, then, we’ll explore Aristotle’s theory of knowledge in more depth, and discuss how the all-too tempting search for certainty, for finality, will close us off to the Space of Possibility.

By John Driggs


[1] Galileo wasn’t the first to perform an experiment, of course, though his experiment typically marks the beginning of modern physics.

The Greek philosopher Empedocles (c. 490 — c. 430 bc) was among the first to devise an experiment. Empedocles, like Democritus, believed that air, though it is invisible, is a material substance. So, he designed a simple experiment to test this claim. By covering the top hole in a water clock and then submerging it in water, he showed that water could not enter the clock through the side holes. The water can’t enter, he claimed, because the clock is filled with air. You can do this experiment for yourself with a straw. Just cover the top with your thumb, dip it in water, and notice that water can’t enter the straw. If you release your thumb, however, the water will push the air out the top.

Another Greek named Eratosthenes (276–194 bc) — the director of the great library of Alexandria during the Hellenistic Period — also performed a rather simple experiment. He read in a book that in the southern part of Syene (modern Aswan, Egypt), at noon on summer solstice, vertical sticks placed in the ground created no shadows. Curious whether the same would hold true in Alexandria on summer solstice at noon, he threw some sticks in the ground to see. To his surprise, there was a slight shadow. Many people might easily ignore this odd discovery. But not Eratosthenes. He thought that this lent support to the claim put forward by a few Greeks before him that the earth must be curved. If so, he realized that he could calculate the size of the earth using just two measurements: the distance between Syene and Alexandria and the angle of the shadow in Alexandria. So, he first measured the angle of the shadow in Alexandria, which was seven degrees, and then hired a man to pace out the distance between Alexandria and Syene, which came out to be eight hundred kilometers. Now, he just had to perform some basic math. If you imagine the two sticks intersecting at the middle of the earth, the seven-degree angle created by the shadow in Alexandria should equal the angle of the two lines intersecting at the middle of the earth (imagine a sideways Z) — that is, the distance from Syene to Alexandria is equal to seven degrees of the earth’s complete three hundred and sixty degrees. Seven degrees therefore covers about one-fiftieth of the earth’s circumference, which makes the earth’s total circumference about forty thousand kilometers (fifty times eight hundred kilometers — the distance between Syene and Alexandria). What a badass. With two sticks, a pair of legs, and a healthy curiosity, Eratosthenes estimated the circumference of the Earth with remarkable precision.

[2] Charles Darwin, More Letters of Charles Darwin, edited by Francis Darwin and A.C. Seward, Appleton, New York (1903), volume I, p. 195.

[3] Descartes, 1640 letter to Regius, AT 3:65.

[4] Descartes, Replies 7, AT 7:537.

[5] Descartes, Med. 1, AT 7:20; Med. 6, AT 7:77; Med. 3, AT 7:39.

[6] Descartes, Med. 5, AT 7:69; Med. 3, AT 7:48ff; Med. 5, AT 7:71