Theory of Knowledge

TOK is the illegitimate child of Philosophy and Psychology
— A sarcastic IB student

Whilst this quotation sounds rude to TOK-lovers (like myself), there is some amount of truth hidden in this claim. TOK contains much epistemology, but not with the traditional terms - there are TOK specific terms that you need to get familiar with. For instance, all IB students should be familiar with all of the AOKs and WOKs. There are also some rather psychological questions that are asked in TOK, such as when discussing the WOK of Memory - so it doesn’t hurt to know some Cognitive Psychology as well.

Anyhow, here are my top tips and key thinkers for TOK students around the world. Also, check out my summary of pivotal key thinkers that I cited in several of my own TOK assignments. These include: St Thomas Aquinas, Yuval Noah Harari, Karen Armstrong, C.S. Lewis, Elizabeth Loftus, Jared Diamond, Noam Chomsky, Michael Sandel, St Teresa of Avila, and St John of the Cross.


Complete assignments early - This goes without saying for most subjects, but it is most important in TOK, because you can really invest a lot of time into the presentation and essay early on, so you don’t need to stress about them during exam season. Many schools I’ve heard of start TOK really late, so I would really recommend doing TOK early - it gives you a huge advantage over everybody else. For the Essay, start researching as soon as IB releases the prescribed titles in grade 12. For the presentation, start ASAP - it can be on anything you choose - so long as you formulate a strong research question.


Presentation: Pair up! - I don’t care what your teacher says you can do - in theory, yes - you should be able to do a good TOK presentation by yourself and in a group of three. In practice, however, I have never seen a good single or group-of-three presentation. Since you get 10 minutes per person, a single presentation can never be as thoroughly in-depth as a 20-minute couple presentation. Three makes a crowd, and a 30-minute presentation is bound to be boring. I did my presentation with a partner and scored 10/10 - and have seen other pairs do very well.

More importantly though, presenting with a partner helps you learn from the “expertise” of the other person - especially if the partner has other HLs than you do. Also, it obviously helps you build collaborative skills. It’s just better to get this done in pairs - there are so many incentives that will help you out.


Critique methodologies in the AOKs - The Scientific Method is a popular one that never gets old - look for the implicit premises hidden in the way we find knowledge in this particular AOK. For Natural Sciences, the Scientific Method presumes that we can know best through sense perception and inductive reasoning - that’s why experiments are conducted over and over again. Is there anything wrong with this methodology? For instance, is everything able to be tested using empirical evidence and sense perception? How about emotions, for instance?

An obvious methodology in Religious Knowledge Systems is telling parables and allegories full of figurative language. In my final TOK essay, I argued that this methodology relies on appeals to the collective imagination. An interesting question we might ask about religious traditions is - what happens when the times change and this collective imagination also changes? For instance, when Jesus is called “Lamb of God” in the Gospels, this appeals to the collective imagination of ancient, second-temple-Jews and evokes imagery of sacrifice. To the modern reader, the image evokes meekness and a cuddly farm animal - a hearty meal at best.

All the AOKs have their characteristic methodologies, which are worth exploring in TOK, which asks “how do we know?” constantly - to break down that question, the methodologies we use in the various AOKs and the implicit ideas that construct these methodologies is important to take note of.

Suggested Key Thinkers

St. Prof. Thomas Aquinas OP (University of Paris)

Apotheosis of St Thomas Aquinas by Francisco de Zurbarán (1631)

Apotheosis of St Thomas Aquinas by Francisco de Zurbarán (1631)

Known as one of the greatest thinkers of Christendom, Thomas Aquinas, born in the Papal States, studied and taught throughout Western Europe. He is well-known as a philosopher in the scholastic tradition, and for his natural theology. His quinque viæ (five ways) are most quoted in academics, which expound five deductive arguments for the existence of God. As such, Aquinas is most invaluable to TOK, as he shows reason as a WOK in Religious Knowledge Systems, as opposed to merely faith or imagination.

The way he writes, for instance, in his infamous works, Summa Theologiæ and Summa Contra Gentiles reflects the use of deductive reason as a WOK in RKS. He poses a question, lists a series of objections before responding in his infamous “respondeo” (I respond that). This shows the academic listening to other arguments, and at best, stating the opposing arguments better than opponents can. This is not only a good example for our TOK presentations and essays, but also a great example for us as IB students. When in the heat of argument (especially with AP or A-level students), we knock down strawmen. However, this Doctor of the Church teaches us to argue properly.

He is considered influential to the development of the natural sciences, as his proposition that truth cannot contradict truth suggests that studying the natural world is compatible with Biblical and theological studies. For me personally, the great saint is a powerful endorsement of studies in both theology and the sciences.

Therefore it is necessary to arrive at a first mover, put in motion by no other; and this everyone understands to be God
— In Summa Theologiæ (First Part, Question 2, Article 3)

Prof. Yuval Noah Harari (Hebrew University of Jerusalem)

As an historian educated at both the Hebrew University of Jerusalem and at Jesus College, Oxford, Prof. Harari is particularly interested in what he calls “imagined orders”, such as money, human rights, legal systems, nations, and (in his argument), religions, which exist only in our collective imaginations. In his widely influential book Sapiens: A Brief History of Humankind, he argues that the distinguishing elements of humans is their ability to create and believe in imagined orders. This argument is especially fitting for imagination as a WOK - we typically associate imagination with literature or the arts, but Harari’s argument (which I also expanded in my own TOK essay) suggests that imagination extends beyond these AOKs to other areas, such as economics, religious knowledge systems, and ethics.

The sequel to this book, Homo Deus: A Brief History of Tomorrow expands his line of thought to how humanity might change in the future, with the increased fusion of imagination and reality, as the boundary between the two are blurred through technological advancements in the fourth industrial era.

There are no gods in the universe, no nations, no money, no human rights, no laws, no justice outside the common imagination of human beings.
— Sapiens: A Brief History of Humankind (pg. 31)

Karen Armstrong (Charter for Compassion)

In compassion, when we feel with the other, we dethrone ourselves from the centre of our world, and we put another person there.

Armstrong, originally a Roman Catholic religious sister, gained the rare honour of a “Congratulatory First” in English Literature at St Anne’s College, Oxford. During her studies, she left her convent. However, some time after her studies, she became interested in various religious traditions, especially because of her time in Jerusalem, in which she saw the uneasy coexistence of the three major Abrahamic traditions.

Her major contribution to religious studies, as well as her Charter for Compassion are widely regarded as vital starting points in interfaith dialogue. In the context of TOK, Armstrong is a pivotal key thinker because she provides several real life examples of how Religious Knowledge Systems operate in the ancient and modern world. Her main argument throughout is that compassion is central to all religious traditions, and that interpretations that are not grounded in compassion are invalid.

Whilst many religious scholars and theologians would find this view rather oversimplistic, the way she argues her points seems to be most relevant to TOK students. The very fact that she cites religious verses to support her point, for instance, exemplifies a methodology in religious knowledge systems. Furthermore, her point that “belief” in religious traditions entails a change in behaviour also portrays a different way of thinking when approaching religious traditions - rituals are a substantial methodology in RKS.

Her main argument regarding religion and compassion in both her TED Talk and Charter represents a significant overlap between RKS and other AOKs. In other words, her argument acknowledges that religious worldviews profoundly influence how we think about other matters.

Professor Clive Staples Lewis (Oxford and Cambridge)

Widely known for both his English Literature, Ethics, and Theology, C.S. Lewis originally studied at University College, Oxford, where he later taught. After participating in the First World War, he also taught at Magdalen College, Oxford.

His notable novels in English Literature include The Chronicles of Narnia, The Great Divorce, and The Space Trilogy. Most of his novels contain profoundly theological themes, and are well known for the fantasy that leads to deeper moral and theological truths. As TOK students, his literature is worth using as real-life examples as part of the AOK Arts. For instance, one could argue that the reason C.S. Lewis was such a successful author is because he is not very preachy in the way he delivers his work, but rather uses the fantasy to subtly deliver his deeper truths. In other words, he readily allows readers to suspend their disbelief by appealing to their collective imagination. This is a key methodology used in the Arts.

However, C.S. Lewis was also vibrant as an ethicist and theologian, both of which are deeply relevant for TOK students. His flagship book, Mere Christianity (which is apparently a compilation of his BBC radio talks) is very readable, and explores his views on ethical knowledge, as well as several formal and informal proofs for the existence of God. For my TOK essay, I cited Lewis’ argument that there is a “law of right and wrong” that we do not “need to be taught”. In other words, Lewis’ argument in TOK terms, is that ethical knowledge is largely known by intuition. For Lewis, despite minor differences between cultures, the ethical code is surprisingly similar in all cultures. I found this to strongly contrast with Harari’s argument that the primary WOK in Ethical Knowledge is imagination.

C.S. Lewis is a pivotal TOK thinker because he shows how Religious Knowledge Systems interact with the other AOKs, as well as giving systematic views on which WOKs are used to know in each of the AOKs he covers.

This law [of right and wrong] was called the Law of nature because people thought that everyone knew it by nature and did not need to be taught it.
— in Mere Christianity (pg. 9)

Professor Michael Sandel (Harvard University)

Certain moral principles have already begun to emerge from the discussions we’ve had.
— in the Justice lectures. Sandel has a unique style of teaching, which involves asking questions and engaging with the audience.

As the quintessential Political Philosophy professor, Sandel studied first in the US, and then at Balliol College, Oxford as a Rhodes Scholar. His work ranges from ethics to political philosophy to economics, and is easily one of the top key thinkers of our times.

Though his work is very wide-ranging, his book What Money Can’t Buy: The Moral Limits of Markets is fascinating, as it shows how society as a whole is stretching the limits of the market to encompass what we previously would have considered “invaluable”. He explains that money is “crowding out” some of the “attitudes and norms worth caring about”. His book is very approachable, as he gives rather light-hearted examples that reveal a deeper, implicit tension between the market and values, and explains subtle philosophical and ethical implications.

As TOK students, looking for strengths and limitations to the Ways of Knowing, it is possible to notice Professor Sandel’s argument on the market demonstrates the limitations of reason in the human sciences. As he noted, economists (and I might add, other social scientists) often assume that money does not change the nature of the goods being exchanged. Yet, beyond rationality and measurement, even intuitively and emotionally, most people understand that certain goods (eg. friendship) are changed when they are bought and sold. Therefore, an interesting TOK argument to make could be that reason is limited and must be supplemented by other WOKs.

His largely influential Justice lectures are worth listening to as well. Readily available for free on YouTube, his lectures discuss deep, philosophical ideas about what it means to live the good life. Also, though I have not read it myself, I hear that his book that accompanies these lectures is also very worthwhile to read.

Prof. Elizabeth Loftus (UC Irvine)

A cognitive psychologist, Loftus frequently discusses the implications of psychological discoveries on memory, especially in the legal field. One of the assumptions the entire legal system holds is that memory is reliable. Hence, many legal cases are decided upon due to witnesses.

However, Loftus questions this very assumption. In this sense, she is a great exemplar for TOK students, as she shows that we should discern the implicit premises of the AOKs and question these.

Loftus is particularly useful in TOK because she examines the WOK memory in great depth. In particular, she shows that it is unreliable, as false memories can be created. In one notable study, Loftus and Palmer (1974) shows that even a single verb in a leading question can be suggestive and lead to different memories. Participants gave different speeds based on different leading verbs, and the proportion of participants answering that they saw glass was higher when verbs with more violent connotations were used.

In other words, she shows that memory, very much unlike a video recording, is reconstructed and prone to bias. She suggests, then, that since memory is unreliable on its own, it should be supplemented with other Ways of Knowing, such as DNA evidence (reason).

The results of this experiment indicate that the form of a question can markedly and systematically affect a witness’s answer to that question.

Prof. Noam Chomsky (MIT, Arizona)

There are very deep and restrictive principles that determine the nature of human language and are rooted in [...] the human mind
— in "Language and Mind" (2006)

Highly influential in both his political activism and linguistics, Chomsky is a pivotal TOK thinker, who is very well-known in the academic world.

As a political thinker, Chomsky is known to have participated heavily in anti-war protests and Occupy Wall Street, as well as in more global political challenges. His pivotal political contribution for TOK students, however, is not so much his left-leaning political stances, but rather, his interesting views on “Manufactured Consent” - that is, how the media is owned by corporations, and therefore represents an established view of the state’s ideology, rather than a truly free discourse. He argues that our consent in politics is not truly free, but rather manufactured by the interests of the state and media. Chomsky, in this sense, is a fundamental model for TOK students, as he teaches us, by his very example, to question the implicit premises of our current culture, which is driven heavily by the media.

As a linguist, Chomsky’s most famous contribution is on innate language and universal grammar. He influentially argues that the capacity to use language is innate. He shows that similarities between languages shows that grammar is essentially universal. He shows that the remarkably fast language learning capacity of children, despite “imperfect and degenerate samples”, is due to an innate capacity to learn languages. To use the TOK terminology, Chomsky’s argument concerns the role of intuition - what we know intrinsically - when it comes to language.

Chomsky is both a fascinating key thinker to listen to, as well as a strong TOK thinker to use in essays. In many ways, his views on intuition can be contrasted with Harari’s views on imagination, which may be worth exploring further in TOK assessments.

Prof. Jared Diamond (UCLA)

Originally trained as both an anthropologist and a physiologist, Diamond fuses several topics together in both his books and his lectures. His books are very readable, and he is very relevant to TOK, as he shows how AOKs at their best are profoundly interconnected.

In his book, Why is Sex Fun?: The Evolution of Human Sexuality, Diamond explores the WOKs of emotion and intuition in some depth, as he explores how emotions such as pleasure are intimately connected to our very biology. Through exploring the significant differences between humans and their close primate relatives, such as parental care for the young and concealed ovulation, Diamond explains that these distinct features of human sexuality are driven by our biology and anthropology. This is fascinating, as Diamond contrasts human sexual practices with that of other animals to question the implicit assumptions we take for granted in human behaviour, such as monogamous marriage.

In another book, Guns, Germs and Steel, Diamond gives an overview of human history, especially attempting to answer why there is such a power gap between the Eurasians/North African civilisations and the other civilisations.

Diamond’s interdisciplinary writing, (which also greatly influenced Harari’s style) is interesting for TOK students, as it explores how the AOKs overlap.

Most men and women in most human societies end up in a long-term pair relationship (“marriage”) [...]

Abu Hamid al-Ghazali (Hujjat ul-Islam)

Al-Ghazali in Arabic calligraphy (source: Wikipedia)

Al-Ghazali in Arabic calligraphy (source: Wikipedia)

We are creatures that love to blame the external, not realizing that the problem is usually internal.
— (attributed to al-Ghazali)

An important thinker, especially in Sunni Islam, Al-Ghazali is thought to be one of the greatest philosophers, theologians, and legal theorists in the Islamic world.

Though he was originally well-versed and even lectured in earlier Islamic philosophy, which was based on the ancient Greeks, he eventually came to a spiritual crisis, which led him to live a life of asceticism for some time.

His major contribution to Islamic thought, the Incoherence of the Philosophers marks a pivotal point in Islam, and has been widely controversial. His major argument throughout is that every causal event is caused by the will of God, rather than through material means. Therefore, unlike several earlier Islamic thinkers that relied heavily on Greek Philosophy, al-Ghazali believed that faith is more important concerning metaphysics, and that there had been major shortcomings in the work of Islamic philosophers. Whilst he was happy to concede that philosophical logic (reason) in its strict sense is useful in material aspects, he argued that this tool is not applicable when referring to the divine. In other words, (like any good TOK student should), he heavily questioned underlying assumptions within the methodology of RKS in his time.

In The Alchemy of Happiness, he suggests that in order to seek out the Divine, we must look deep within ourselves. At some superficial level, this resembles St Teresa of Avila’s work (see below), as in contrast to the natural theology advocated by al-Ghazali’s predecessors in Islamic philosophy, which advocates looking at the natural world for God, the major aspects of this work are looking within ourselves in our spiritual lives. In some sense, this in itself is one of the great methodologies in Religious Knowledge Systems, in which looking within ourselves is considered infinitely important.

His work is also pivotal in reconciling Sufism, a type of Muslim mysticism, into mainstream Islam. Sufism contrasts heavily with the reason-based approach to Islam, and emphasises the religious, mystical experience through “integration of outer ritual and inner spirituality” (Urubshurow, 2008). In some sense, this seems to emphasise something of a religious experience, which is fundamentally different to what can be known simply through reason.

As a TOK-thinker, al-Ghazali is priceless, as his work gives a perspective within the Islamic tradition. Personally, I used verses from the Qu’ran to support my arguments in my final TOK essay, but now that I have read about al-Ghazali, I feel that I could have just as well used some of his arguments in my essay, as he shows a major element within the methodology of RKS.

St Teresa of Avila OCD & St John of the Cross OCD

Acclaimed for mysticism and the contemplative life, the two saints were leading figures in founding the Discalced Carmelite Order (OCD). This was a large element in the religious history, as it forms part of the counter-reformation movement.

St Teresa of Avila in particular is often compared and contrasted with St Thomas Aquinas, as they represent two important aspects of the Christian tradition. St Thomas Aquinas represents the intellectual pursuit of Christianity through his reason-based arguments on a wide range of subjects. Rather tellingly, his most well-known transcendent experience occurred after he wrote his major works, in which Christ asks him what he wants for his great theological works, and he responds, “Nothing but you Lord”. By contrast, St Teresa of Avila had her visions before she began her prolific writing. In other words, for St Teresa, it is the religious experience of prayer that moves her to write. In some (albeit imperfect) sense, St Thomas Aquinas represents the WOK of reason in RKS, whereas St Teresa represents a combination of the WOKs of emotion and imagination in our innermost lives. St Thomas represents what reason can achieve in terms of shared knowledge, whereas what St Teresa represents is knowledge that is more personal - the religious experience that comes with prayer and grace.

This contrast may explain why in terms of language, St John of the Cross often uses poetry to describe his main thoughts and why St Teresa of Avila uses eloquent metaphorical language, such as in her Interior Castle, in which she describes our interior as being like a castle composed of many mansions. By contrast, Aquinas’ language is much more straightforward, based on observations on the outside, natural world and philosophical proofs.

For TOK students, the two great saints of the Carmelite tradition portray how Religious Knowledge and the way Religious Knowledge is constructed may differ substantially from other AOKs - it is not simply a reason-based exercise, but also involves a profound, transcendent experience with Divinity.

I thought of the soul as resembling a castle, formed of a single diamond or a very transparent crystal, and containing many rooms, just as in heaven there are many mansions.
— In El Castillo Interior, St Teresa makes an extended metaphor to describe what is, a limitation of language - her internal experience of the divine.

Suggest Your Own Key Thinkers :)

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