How do we know what we know?

In July, I’ll be teaching a course at the Buddhist Library in Sydney on Jayatilleke’s Early Buddhist Theory of Knowledge.

I’ve wanted to do this for some time, as a personal homage to what I believe is the greatest 20th century book of Buddhist philosophy, one whose message is more urgently needed than ever.

We are descending into dangerous time. We have more information than ever before, yet the truth has become more and more lost. The foundational ideals of rationality and science on which our society was built, and which gave us a shared framework for understanding reality, are being torn apart one tweet at a time. Make no mistake, the undermining of truth in favor of pure subjectivity is dangerous, and it threatens us all.

Consider an obvious case such as climate change. In the 90s, in the USA or Australia, there was a broadly based understanding that this was a real problem needing urgent attention. The parties would differ in their solutions, perhaps emphasizing government intervention or market-based approaches. And they would also share an understanding that both the public and private sectors need to be on board to solve it. In such a situation, there is space for negotiation and compromise, and the best ideas might come from anywhere in the room.

Fast forward to today, and one side is still saying, “let’s solve climate change” while the other is saying, “climate change isn’t real”. You can’t negotiate on that. There’s simply no common ground, no shared perception of reality.

What happens next? If we can’t discuss rationally on the basis of truth, then what do we do?

One side will try to gain the high ground by saying, “Everyone’s entitled to their opinion”, “I respect your right to disagree”, “We just have alternative facts”. They will position themselves as the champions of free speech and free inquiry. But what they are really doing is holding themselves unaccountable to the facts.

This kind of rhetoric is persuasive to a point. By adopting the ideals of classical liberalism, they position themselves on the side of openness. What they miss is that classical liberals also believed in the power of rationality and science to discover the truth and resolve differences. Otherwise we are just opining at each other, and the very possibility of rational discourse vanishes. Which is, of course, the point.

When differences cannot be resolved by reason and evidence, what happens? It all sounds nice when we are floating ideas about consequence-free, but our ability to do so is a privilege. I can act like I have a principled stance as to why Black Lives Matter is too extreme. But it’s difficult to argue the opposite point of view when you’ve got a bullet in the head.

And there’s the rub. When truth vanishes, power takes over.

You’re driving with some friends in a car. You reach a fork in the road. Left or right? Do you decide this by establishing a common goal of understanding? Let’s take the quickest route! The most beautiful! The one I’m familiar with! There comes a point where ideas don’t just float about in some nebulous realm of subjectivity. You make a choice or you run into a tree. And if everyone’s choice is equally valid, then the one that wins is the one that has power.

Our institutions of power—police, justice, parliaments, universities—are founded on this understanding, and they try to temper power with reasoned truth. Sure, they often do it really badly, and there is much room for improvement and reform. But at least there’s a theoretical appreciation that certain standards and norms of a shared reality must prevail, lest the state and all its institutions devolve to fascism.

The Buddha didn’t just tell us what the truth was, he showed us how to find the truth for ourselves. There is a place for received wisdom, a place for conversation, a place for individual perspectives, a place for rational inquiry, and a place for liberating insight. All these are necessary and none may be disposed of. Not only that, but they all have a specific role to play, and a relation to each other. His theory of knowledge is rational and evidence-based, but as it includes super-normal states of meditation and liberation, it has a wider and deeper scope than western philosophies.

In spiritual life, we should strive to improve our understanding and deepen our wisdom. Of course it’s true that spiritual truths are subtle and often highly personal. All the more reason why a single truth becomes so precious.

The Buddha by no means endorsed the idea that everyone has their own reality. (Snp 4.12, Bodhi’s translation)

Truth, indeed, is one—there is no second;
a person who understands this would not dispute.
These proclaim their own diverse truths;
therefore ascetics do not speak in unison

Disharmony comes not from the reliance on a view founded in reality, for that is what makes civil and rational discourse possible. Rather, it comes from the embracing of a subjectivist view where my delusion is as valid as your knowledge. When religious movements reject the accountability of the truth, they are taking the first step towards becoming a cult.

The Jatakas (Ja 422) tell the story of the first lie, which arose over the question of patrimony. The true son inherits the kingdom, so for the sake of power, the lie is invented.

This is why the first of the precepts on speech is to tell the truth. It’s only possible to tell a lie if there is an agreed understanding of the truth. If truth is purely subjective, then there is no accountability for the facts. And the precept falls into abeyance.

We can do better, and we must do better. It’s no exaggeration to say that the survival of humanity depends on this. If we allow the truth to continue to slide into irrelevance, we’re over. It’s been nice knowing you. Or did I really ever know you at all?


Looks interesting Bhante. I have Jayatilleke’s book on my reading pile. I might bump it up a bit now. It would be interesting to see if he equates the Buddha’s epistemology with what is known in the west as logical positivism and their verificationist theory. If he does i wonder then how said theory could be salvaged, seeing as how it’s largely been abandoned due to its epistemological holes. There aren’t many logical positivists or proponents of verificationism around these days. I remember Ayer, one of the founders of the movement, later said that “almost all of it was wrong”. I agree that the Buddha had an empiricist side, but I’m unsure about the theory of verificationism (if that is what Jayatilleke claims of course). It would also be interesting to see if he addresses any of the criticisms found in Quine’s “Two Dogmas of Empiricism”.

One thing I did want to say was in relation to this:

We do not yet know why Sasha Johnson was shot. It would be irrational to jump to any conclusions at this point, and so far I’ve read that the police are treating it as a potential gang related shooting which Sasha was accidentally caught up in. The suspects have all been charged so we should know in time. Naturally we wish her a speedy recovery.

PDF is available here. I shall start reading. :smiley:


Take it easy, it’s not for the faint of heart! I’m hoping to make it somewhat more digestible in the course.


It threatens you, who is invested in the success of the current institutions. I am good at direct heart to heart conversation, less so when talking as a institutional mouthpiece. Pure subjectivity (should be really called individual objectivism, nullius in verba) favors me.

I do not agree with this assessment at all. We can still have productive discussion in a small group where people are willing to change their mind and speak heart to heart.

It’s simply the case that the ability of current institutions to arrive at the truth or change it’s mind once proven false is minimal.

I noticed that! Approx 125 pages of ancient philosophy per week between now and July 3rd is going to require a very Stout Heart. :rofl:


(If you don’t read everything, I won’t tell!)

But seriously, his work is very sectional. Yes, it builds towards larger themes, but you can get a lot from just cherry-picking things that interest you. And a not-insignificant part consists of replies to contemporary scholars, which can mostly be ignored.


Here’s a course outline, which I sent to the Buddhist Library, but it’s not up yet. (Subject to change!)

Early Buddhist Theory of Knowledge


Early Buddhist Theory of Knowledge (EBTOK) is a seminal book of Buddhist philosophy by the eminent scholar K.N. Jayatilleke. A student of Lugwig Wittgenstein, Jayatilleke applied a rigorous analytical style to examine the early Buddhist approach to one of the central problems of philosophy: how we know what we know.

Jayatilleke’s work is dense and he does little to accommodate his readers. While his vast erudition and fluency in philosophy East and West has rarely been equaled, today his influence is mainly felt as the teacher of the teachers. Shortly after his time, his constructive historical approach lost favor as philosophy took other directions. In Asia, Buddhism grew inward-looking and traditionalist, while in the West, sterile postmodernism and wan subjectivism rule the day. The Buddha’s critique of all these approaches is, ironically enough, spelled out in Early Buddhist Theory of Knowledge.

Jayatilleke’s work stands as an example of what might have been, and might yet be. What if we were to take the Buddha’s teachings seriously, neither as a bolster for nationalist pride, nor as a balm for agitated nerves, but as something more meaningful? A guide to reality; or, more to the point, a guide to how we might know reality for ourselves.

We living through an epistemological crisis. We have access to unprecedented knowledge, yet are less sure than ever how to discern what is right and wrong, what is true and what is false. The Buddha was constantly engaging with people of all different backgrounds, making competing claims as to what was true and what was false. He showed a path through the thicket that is always balanced, reasonable, and effective. To learn from him is not merely to appreciate how wise he was in his time, but to understand how to manifest the same wisdom in our time.

The course

The course takes five classes, which will cover all the chapters of EBTOK. Try to read all relevant chapters before the class. You can skip the bits with lots of Pali, or that get into strictly logical analysis, or that develop comparisons with ancient Greek philosophy (unless you’re into that sort of thing.) But if you want to get something out of the course, read as much as you can. If you read it before, then take the course, then read it again, I think you’ll get a lot out of it.

I try to structure the course with a heavier reading load at the start, so that there will be more room for discussion as the course progresses.

1: The Buddha in context

Studying the Buddha without knowledge of his contemporaries is like listening to a stranger talk on the phone, without knowing who they are talking to or what the other person is saying.


Parts 1, 2, and 3 “The Historical Background”.

Some terms to know

If you don’t know them, look them up!

  • Buddhist modernism
  • Early Buddhism
  • Empiricism
  • Ontology
  • Epistemology
  • Upanishad
  • Veda
  • Sophistry


  • Vedic knowledge—knowledge stems from faith in tradition
  • Materialist knowledge—empirical and rational critique of metaphysics
  • Skepticism—knowledge is impossible


  • Do Buddhists blindly believe based on tradition?
  • Do non-Buddhists do the same?
  • Is there a role for traditional knowledge?
  • Are modern materialists similar to those found in the Suttas?
  • What about skepticism? Are the ancient skeptics like moderns or not?

2: The Buddha’s critique of non-Buddhist attitudes to authority and reason

Is knowledge something that is inherited from the ancients? Or can we discover the truth by logical inquiry?


Parts 4 “The Attitude to Authority” and 5 “The Attitude to Reason”.


This section focuses on the means of knowing that were championed among the non-Buddhist schools, especially insofar as they were subject to criticism by the Buddha. The specific terms used in the Suttas are analyzed and found to correspond to terms used in non-Buddhist texts.


  • Which is better: obedience to authority? or the whims of the mob?
  • Does authority admit of degrees?
  • How do we assign authority today?
  • Are all opinions equally valid?
  • How do we test our own opinions?

3: The uses and limits of logic and meaning

Rather than falling back on a single source of absolute knowledge, the Buddha allowed a limited and relative value to multiple ways of knowing. Not just that, but he showed the relation between them and how they work together to firm up knowledge.


Parts 6 on analysis and meaning, and 7 on logic and truth.


Finally we turn to the Buddha’s own constructivist and empirical approach to knowledge. Having dismissed the absolute reliance on skepticism, logic, or authority, the Buddha allowed each of these in a reasonable and balanced way. We look at the difference between meaningful and meaningless statements, and discuss the Buddha’s fourfold logic.


  • Is black and white logic always wrong?
  • What’s the difference between a statement that is incorrect and one that is meaningless?
  • Can something be correct and meaningless?
  • How do we know when to use the different methods of answering questions?
  • Can these approaches be applied to social media?

4: Authority and reason within Buddhism

The Buddha himself claimed authority in matters of Dhamma, and that must be balanced with the role of reason and evidence.


Part 8.


The Buddha denied omniscience, yet spoke with deep authority. His words are regarded as the authority on Dhamma, yet we are simultaneously urged to test them and see for ourselves.


  • What happens when we disagree with the Suttas?
  • Did the Buddha make mistakes?
  • What happens if we meditate and it doesn’t work?
  • What kinds of modern evidence do we have that the Buddha didn’t?

5: The means and limits of knowledge

More than reason or authority, the Buddha emphasized direct personal experience.


Part 9.


Experience is a crucial part of knowing, but itself is not infallible. Meditation removes the things that distort experience, but even then, it may be misinterpreted. Experiential knowledge is also inferential, and subject to verification. Extra-sensory perception is a form of empirical knowledge. Controversially, Jayatilleke ends by implying that Nibbana is a transcendental reality beyond the empirical.


  • When is experience unreliable?
  • How does experience relate to reason?
  • Is cause observable?
  • Is it valid to describe the Buddha as an empiricist?
  • How cool is Nibbana?


I see what you did there! :wink:


Thanks for this link, Gillian. Over 500 pages, and could the font be any smaller? I’d like to read this but the page looks like it has tiny wordlike ants on it. :slight_smile:

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Zoom in on the page till you’re down to 50 words a page … think how many pages that’ll make it. :rofl:

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Awesome! Note that since it is an in person only event, some of us would wait for the recordings uploaded online. Maybe I am being used to the bright side of the pandemic.

For the text, Jayatilleke’s masterpiece, it seems that I have a PDF with slightly higher resolutions compared to the above link:

Hope this would help, @UpasakaMichael. One can also buy the book at reasonable prices online, shipped from some Indian bookstores.


@UpasakaMichael: we have lots more reading time.



@FelixC Thanks for this link I can read the text now :slight_smile: Now having read the first paragraph under The Historical Background I: Vedic , and not understanding the first words of this book, I want to cry. :scream_cat:


Jayatilleke doesn’t make it easy. But let me see if I can help.

The book begins with a reference to the “history of thought” in Greece. This is, of course, the basic framework for the development of western philosophy. So Jayatilleke is positioning this book as one that is equally fluent in both east and west. This is a rhetorical strategy, acting both to make the work more acceptable to western philosophy departments (which are still overwhelmingly white) as well as leveraging the prestige of western thought in Asia.

He is writing for philosophy students who are assumed to be familiar with the background.

The opening sentence claims that we can identify a historical sequence: from mythology to metaphysics to empiricism.

In reality, the historical situation is not so clear-cut, but still, this is, I think, a fair enough generalization. But what do these things mean?

“Mythology” should be understandable to anyone who’s been following my work. It refers to the body of narrative, passed down among a people, that tells their story, particularly regarding the origin of the world and their place in it.

Such stories typically include many events and entities that we would regard as “supernatural”, i.e. literally “above nature”. Entities such as the gods are attributed qualities such as immortality and various forms of mysterious powers unlike anything seen on earth.

So then people start to question this. Who exactly are these gods? Why can’t we see them? Where do they live? How come the accounts of them are so varied and contradictory?

One influential train of thought at this point is to look to the stars. See, they are immortal, they never change. Things down here fall under the influence of gravity, but up there, gravity doesn’t seem to work.

So astronomy, which of course was one of the most highly developed sciences in the ancient world, seems to provide some support for the reality of the gods.

It seems, then that there are two worlds, or two aspects of existence. The “natural” or “physical” world down here, full of rocks and humans and oceans, all subject to decay and disease, and another “super-natural” or “meta-physical” world up there, full of stars and gods and light, and not subject to worldly travails.

This argument was given a thorough rational foundation by Socrates in his talk of “forms”. For each kind of thing that we can see, there is another reality, a “form” of the thing, which is more real. What we can see here are merely the shadows of these forms. In this way the metaphysical realm becomes more real than our realm.

Then question then arises, how do we know this? We know that “this is a tree” because, well, there it is. But how do we know what the “form” of a tree is? Such questions fall within the field of study known as “epistemology”, i.e. the study of how we know what we know.

Socrates pointed out that the senses can be unreliable. Sometimes we see things that are not there, or mistake what we do see. On the other hand, he argued, what we can know with true certainty is logic. If I see an orange tree and someone asks, “how many fruit are on it”, I can try to count and say “six”. But it is of course entirely possible that I will miss a fruit, or double count one. On the other hand, if someone asks, “what is three plus three”, I know the answer with absolute certainty, and it will be the same in any time and place. (Socrates believed that such knowledge was true and innate because we are merely recollecting things that we learned in our past lives, but later Western philosophers tended to gloss over that part.)

His approach was very influential, but came under increasing criticism over time, especially with Kant’s Critique of Pure Reason. The basic problem is that, while the form of rational argument conveys the impression of certainty, in fact the premises of the argument must ultimately be based on sense impressions. Children, for example, learn the number “6” by counting six things. Thus the apparent certainty provided by purely rational argumentation turns out to merely be hiding uncertainty in the premises.

So to advance epistemology we have to consider more closely the kinds of knowledge provided by the senses, and what valid inferences may be made from them.

This form of epistemology is called “empiricism”, and it is the foundation of modern science, ever since Galileo said, “Measure it. It it can’t be measured, make it measurable.” (Not sure if this is a real quote!)

One of the tendencies of western empiricist thought is to increasingly question and reject the “metaphysical” realm, a tendency brought to its conclusion in the contemporary “logical positivist” school, which dismissed any metaphysics outright.

Jayatilleke will go on to advance the argument that the Buddha not only pre-empted the empirical philosophy by thousands of years, but his form of empiricism (“by no means identical” with that of the West) is more broadly based, since rather than exclude “supernatural” events, it finds room to include them (or at least some of them) within the empirically-known realm of nature.


Sadhu, Bhante, and thank you for taking the time to write this excellent essay and explanation. I feel I now have something of a scholarly roadmap with which to start the journey through Jayatilleke’s book.


This looks like a really interesting and rich course!
I am really excited for it!

I hope it will be recorded and put online.
I would love to come in person, but unfortunetly I have work on at the time of the talks.

First, if it is online, where will it be posted?

Second, can we have a forum (on Suttacentral, or elsewhere) for asking questions about the readings each week? Both clarification questions and substantial questions which can start philosophical discussions.

I have been part of a few philosophy seminars with attached forums in my studies (I just did a philosophy honours year partly online during covid), and I have seen some things that work well (and things that don’t).

My philosophy professors often ask everyone to submit two questions on the readings each week. My professors often use these questions in various ways, such as the teacher incorporating the ideas from the questions into the seminar, or the questions being the seeds of discussion groups among students, or just using philosophical questions as a way for students to deeply engage with the readings, or other things. Having a place to put questions each week might be a good way to allow some people to engage deeply with the philosophy, text and course.
(I assume it would best as an optional thing in this context, as this isn’t a formal university class and I assume not everyone in the diverse audience would want to submit questions.)
It would be really nice to have a place for questions, and perhaps a place for discussion (either in topics, or in threads starting from questions).

I would love to help set up a forum for questions and discussion for this course!


I understand what @sujato meant is that the group that says “Climate change isn’t real” has already been presented with a deluge of facts but has repeatedly chosen to ignore or disbelieve empirical evidence and their minds are not going to change. Therefore “You can’t negotiate on that. There’s simply no common ground, no shared perception of reality.”


Yes the recording will be uploaded in due course.


No, thank you! It’s made me think through more carefully the approach I should take in the course.

That sounds like a great idea!

Okay, let me think about that.

Well great. Pretty sure we can do it here, so let’s maybe think about a way to do that.