我沒有對下文所呈現思路和觀點置喙的功力；但相信它們值得深思。Happy reading and contemplating.

此文可以和拙作《淺談dialectic》以及我跟孫隆基教授對談諸文中關於「辯證觀」部份參照；孫教授大作請見此處。此外，在以下的「索引」外，請使用正文中的「超連接」。

索引：

validity (logic)：(論證)「合格」；「論證過程」在形式上符合推論格式或邏輯規則。

The paradoxes at the heart of reality

An interview with Graham Priest

We believe things can’t be both true and false, it can’t be both raining and not raining at the same time. Philosopher Graham Priest, however, thinks differently. In this interview, he argues true contradictions are an intrinsic part of reality.

Most of us think in binaries: either it’s raining or it’s not, things are black or white, true or false. The philosophies of Frege and Russell in the 20^th century formalised these binaries into the very logic of our thinking. Graham Priest pushes back against this. There is a huge variety of paradoxes which have puzzled philosophers throughout the ages, and that old view that contradictions are always false has yet to be justified. In this interview with the leading theorist of dialetheism we discover how it can be raining and not raining at the same time.

So, Graham what is the argument? Some commentators have argued that you seem to be saying that paradoxes are not just linguistic or conceptual issues, but that they exist in the world itself?

I don’t think I have ever said that. What I have said is that some contradictions are true (dialetheism, as it is now called). What makes a statement true is, in general, a combination of what words mean and how the world is. So ‘Australia is in the Southern Hemisphere’ is true partly in virtue of the meaning of ‘Southern Hemisphere’, and partly in virtue of some geographical facts. Many true contradictions are no exception to this general rule.

What was your intellectual journey towards dialetheism? Was there a specific moment or experience that convinced you that true contradictions are a fundamental aspect of reality?

I was trained as a mathematician. My doctorate is in mathematical logic, and I was as classical a logician as anyone could be. Any logician must engage with some of the most profound mathematical results of the 20th century, such as Gödel’s Incompleteness Theorems. These are closely related to the paradoxes of self-reference. So I became interested in these. These paradoxes have been discussed by logicians for nearly two and a half thousand years, and there has been no success in solving them—at least if success is judged by consensus.  These paradoxes are arguments for certain contradictions. Most have assumed that there must be something wrong with the arguments. I started to think ‘maybe this isn’t true: these arguments just establish their contradictory conclusions’. So I started to investigate this possibility, its ramifications and applications. After a period of time, I became persuaded that, despite being highly unorthodox, this is a very sensible view.

How do you define a paradox? Are there criteria that distinguish a "true" paradox from one that merely appears paradoxical due to linguistic confusion or logical error?

A paradox is an argument which appears to be sound, but which ends in a contradiction. If the argument really is sound, the contradiction is true. If not, there is no reason to believe so. Of course, all the hard work has to go in determining whether the argument is sound. There is no magic bullet to determine this.

The Law of Non-Contradiction, that something has to be true or false, is a foundational principle of classical logic. How do you respond to those who argue that abandoning this law leads to an incoherent or meaningless view of reality?And how do you counter the explosion argument in favour of the law of  Non-Contradiction, the idea that if we allow contradictions to be true we can reach any conclusion we want? Can you provide a concrete example of a true paradox in the world?

Well, what is called classical logic is a logic invented by logicians such as Frege and Russell at the turn of the 20^th century—though it has some things (but only some things) in common with really classical logics. those of Ancient Greece, for instance.

If someone claims that abandoning the Principle of Non-Contradiction leads to an incoherent or meaningless view of reality (whatever that is supposed to mean), the onus is on them to make good this claim. I have never seen a successful argument for this.

The argument for Explosion presupposes that truth and falsity are exclusive. Hence an argument against true contradictions on the basis of Explosion begs the question. There are now many well understood formal logics which do not have this presupposition. They are called paraconsistent.

There are many possible examples of the kind you ask for (though of course they are all contentious). One is the sorites paradox. Take a long sequence of colour strips such that the colour of each is indistinguishable from that of the strips immediately adjacent to it, but such that the first strip is red and the last is not (say, blue). The strips in the middle of the sequence are symmetrically poised between being red and not being red. One may argue that they are both.

So, taking an example like "It's raining and it's not raining." How would you defend the claim that this could be a true paradox? What are the implications for our understanding of truth and reality?

This is a standard example taken from another sorites paradox, concerning a slow but continuous transition from a heavy downpour to the rain having stopped. Like the paradoxes of self-reference, there is no consensus about how this should be solved. A dialetheic solution is one of them, but of course there are others. One just has to engage in the discussion of which solution is best. For what it is worth, when ordinary people (not philosophers!)  are interviewed about what to say of the such borderline cases, many are quite happy to say that it is raining and not raining.

What are the implications? That some contradictions are true, and that reality is such as to make them so.

You’ve argued against the transitivity of identity, the idea that everything has to be identical with itself. How do you address the criticism that rejecting this principle undermines the coherence of identity itself? Could you explain how this view aligns with, or contradicts, your commitment to realism?

If someone claims that rejecting transitivity undermines the coherence of identity (whatever that means), the onus is on them to justify the claim. The transitivity of identity is certainly a standard assumption, but that is not good enough. One thing we have learned from the history of philosophy, logic, and science, is that standard assumptions are often false. Once such an assumption is challenged a case needs to be made for it.

Whether or not I’m a realist might depend on what you mean by ‘realism’. The word gets used to mean many different things. But in any case, I see no obvious connection between the transitivity of identity and realism—whatever that might mean.

In embracing paradoxes as real, what are the ontological commitments that follow? How does this impact your view of metaphysics, particularly regarding concepts like objecthood and identity?

I’m not sure there is anything much more to say about this. Since I am a dialetheist, I think that some objects are contradictory. That says nothing about their objecthood per se. Dialetheism does not, in itself, imply that identity is non-transitive. It is quite compatible with a standard view of identity. However, in one of my books I applied it to give a non-transitive theory of identity.

So, what are the practical consequences of accepting that true paradoxes exist? How should this influence our everyday reasoning, decision-making, and scientific inquiry?

This is a big question, but the outline of an answer is as follows. Whenever we hold a view on some matter, it is usually embedded in some general theory or other—maybe a confused one. The rational thing to do is to accept whichever is the best theory, and so the answer it gives.  If one is not a dialetheist all inconsistent theories are off the table; but with dialetheism, some may well be. We still choose the best theory, but now this may be an inconsistent one.

Mathematics and science are fields heavily reliant on consistency and non-contradiction. How do you see dialetheism affecting these domains? Are there areas where embracing paradoxes could lead to new insights or breakthroughs?

No, this is not true. First, we now know that there are coherent mathematical theories based on non-classical logics. Those based on a paraconsistent logic will be inconsistent. Moreover, inconsistent theories have been accepted by scientists. The most obvious example of this is classical dynamics. For about 200 years, this was based on the infinitesimal calculus, which was well known to be inconsistent.  Scientists will accept whatever theory produces the right empirical results. If this is inconsistent, so be it. True, for the last 200 years scientists have not deliberately constructed inconsistent theories; but now that we have well-established non-classical mathematics, perhaps they will be.

If contradictions can be true, what does this mean for ethical reasoning and moral philosophy? Could there be true moral paradoxes, and if so, how should we navigate them?

Yes, there would appear to be normative dialetheias, where you ought to bring it about that something, and it is not the case that you ought to bring it about. If this is so, you just have to live with the contradiction, and take the consequences.

What are the most common objections you face regarding dialetheism, and how do you typically respond to them? For instance, how do you defend against the claim that accepting contradictions leads to logical and practical chaos?

The traditional arguments against dialetheism are those provided by Aristotle in his Metaphysics and they are pretty hopeless, as most modern commentators now agree.  Probably the most common objection now is that dialetheism implies that everything is true. This depends on the principle of Explosion. The validity of Explosion presupposes that truth and falsity are exclusive, and so begs the question.  There is no logical chaos in a paraconsistent logic. Such logics are as precise and mathematically articulated as any other contemporary system of formal logic.

Perhaps the other most common objection is: ‘I just don’t see how a contradiction can be true’. That says more about the speaker than the view itself. Many people found the Special Theory of Relativity hard to accept at first because they just ‘couldn’t see how time could run at different rates in different frames of reference’. In both cases, you just have to get used to the new theoretical framework.

Looking forward, what do you see as the future of dialetheism in philosophy? Do you believe that your views will gain wider acceptance, and if so, what shifts in philosophical thought or practice do you anticipate?

I certainly hope so, but of course the future of philosophy—as of so much else—is inherently unpredictable. Philosophical thinking (at least in the West) has been constrained by the dogmatism of consistency since Aristotle. Once these blinkers are off, who knows where philosophy could go?

How has your commitment to paradoxes and dialetheism influenced your personal worldview? Do you find that it has changed the way you approach life’s uncertainties and contradictions?

Not really. Perhaps the fact that I have had to come to reject something I took to be obvious has made me more suspicious of views which many people (including myself) are wont to take for granted.

What advice would you give to young philosophers who are grappling with the idea of true paradoxes? How should they approach the study of logic and metaphysics in light of your theories?

Approach things with an open mind. Don’t believe something simply because tradition says it is so. Don’t believe something simply because you read it in a book—mine included.  Explore the ideas and look at the evidence for yourself; make your own mind up.


Graham Priest, is a philosopher and logician at CUNY. A key defender of dialetheism, the view that there are true contradictions.

Omari Edwards, is contributing Editor for IAI News, the online magazine of the Institute of Art and Ideas. Twitter: @edwardsomari1

Join Priest alongside other speakers such as Slavoj Zizek, Roger Penrose, and Phillipa Gregory at the HowTheLightGetsIn festival on September 21st-22nd debating topics from consciousness, to quantum mechanics, politics to beauty. Learn more here.

Related Posts:

Experts and charlatans: The role of science in democracy
Science and religion are not in conflict
11 philosophers you don't know about, but should
Hossenfelder vs Goff: Do electrons exist?
On Language and Logic, With Timothy Williamson, Saul Kripke, Romina Padro

Maths, like quantum physics, has observer problems, Edward Frenkel

這篇文章有點啟發性；值得一讀和順著作者思路更進一步或更深入一層。由於其主旨的哲學性高於自然科學性，刊於此欄。


Chaos and cause

Can a butterfly’s wings trigger a distant hurricane? The answer depends on the perspective you take: physics or human agency

Erik Van Aken, Edited by Pam Weintraub, 06/13/24

A slight shift in Cleopatra’s beauty, and the Roman Empire unravels. You miss your train, and an unexpected encounter changes the course of your life. A butterfly alights from a tree in Michoacán, triggering a hurricane halfway across the globe. These scenarios exemplify the essence of ‘chaos’, a term scientists coined during the middle of the 20th century, to describe how small events in complex systems can have vast, unpredictable consequences.

Beyond these anecdotes, I want to tell you the story of chaos and answer the question: ‘Can the simple flutter of a butterfly’s wings truly trigger a distant hurricane?’ To uncover the layers of this question, we must first journey into the classical world of Newtonian physics. What we uncover is fascinating – the Universe, from the grand scale of empires to the intimate moments of daily life, operates within a framework where chaos and order are not opposites but intricately connected forces.

In his bestselling book Chaos: Making a New Science (1987), James Gleick observes that 20th-century science will be remembered for three things: relativity, quantum mechanics (QM), and chaos. These theories are distinctive because they shift our understanding of classical physics toward a more complex, mysterious and unpredictable world.

Classical physics, which reached its pinnacle in the work of Isaac Newton, painted a universe ruled by determinism and order. It was a world akin to a perfectly designed machine, where each action, like the fall of a domino, inevitably triggered a predictable effect. This absolute predictability – a world where understanding the present means knowing the future – became the essence of Newtonian mechanics.

Classical physics not only presented an orderly universe among Newton’s followers, but it also instilled a profound sense of mastery over the natural world. Newton’s discoveries fostered the belief that the Universe, previously shrouded in mystery, was now laid bare, sparking an unprecedented optimism in the power of science. Armed with Newton’s laws and revolutionary mathematics, leading thinkers felt they had finally unlocked the secrets of reality.

In this atmosphere of scientific triumph, Alexander Pope, the great poet of the Enlightenment, wrote a fitting epitaph for Newton that captured the monumental impact of his contribution:

Nature and Nature’s laws lay hid in night.
God said, Let Newton be! and all was light.

Not everyone was excited. In his beautiful work Lamia (1820), John Keats poignantly expressed concern over the loss of mystery and wonder in the face of empirical scrutiny:

Do not all charms fly
At the mere touch of cold philosophy?
There was an awful rainbow once in heaven:
We know her woof, her texture; she is given
In the dull catalogue of common things.
Philosophy will clip an Angel’s wings,
Conquer all mysteries by rule and line,
Empty the haunted air, and gnomed mine –
Unweave a rainbow, as it erewhile made
The tender-person’d Lamia melt into a shade.

The ‘cold philosophy’ of classical physics seemed to ‘unweave a rainbow’, stripping the natural world of its enchantment and mystery. Keats resented the process of scientific rationalisation, which could ‘clip an Angel’s wings’ and reduce the world’s wonders to simple entries in ‘the dull catalogue of common things’.

And yet, the 20th century witnessed a dramatic shift with the emergence of relativity, which redefines our understanding of space and time; QM, which revolutionised our understanding of the subatomic world; and chaos theory. The orderly and predictable world of Newtonian physics, the dream of a mechanical universe ready to unveil her innermost workings, was, happily or not, something of an illusion. In the 20^th century, science revealed a far more intricate, less predictable and, indeed, chaotic universe.

Like the other two pillars Gleick identified, chaos theory challenges our understanding of classical physics. However, unlike QM and relativity, chaos theory operates within a Newtonian framework – it assumes a deterministic reality governed by specific laws. Yet chaos theory reveals a beguiling level of unpredictability, particularly at a macroscopic level.

The unpredictability revealed by chaos theory, seemingly at odds with a deterministic worldview, arises from the complex nature of nonlinear systems.

In dynamical systems, behaviour changes over time. The concept of determinism implies that future states are precisely determined by current conditions, without any randomness or chance involved. However, when dynamical systems exhibit nonlinearity, their behaviour becomes more complex and less predictable. This complexity arises from a disproportionate relationship between input or cause and output or effect.

Consider a simple faucet. At low pressure, water flows in a smooth, or laminar, pattern. As pressure increases, the flow remains steady but broadens slightly. At one critical point, however, marked by no more than a tiny pressure change, we see a ‘phase transition’ – the orderly flow suddenly becomes turbulent, exemplifying chaos: the sensitivity of nonlinear systems like fluids to minor changes, leading to unpredictable outcomes.

Think about the movement of a small pebble rolling down a mountain slope. Tiny variations in its starting point, uneven terrain, soil density, even wind direction can drastically alter its path and final position. For instance, imagine we drop a pebble at a specific location and it comes to rest in another location. Imagine we run a simple experiment, dropping the pebble one millimetre away from where we dropped it in the first place. If the pebble’s movement is slightly altered by external factors like wind, hitting a patch of highly dense soil or a large rock, its speed could increase dramatically, ultimately stopping in an unexpected location 5,000 mm away from where it landed in the first drop.

A parallel in celestial mechanics is the so-called three-body problem, with three bodies in space like the recent Netflix series. Consider two bodies in space: Earth and the Moon. Newtonian mechanics allows us to predict the orbital motions of these two bodies perfectly. Yet, when we add a third body, the Sun, we discover a level of complexity that defies Newtonian predictability. The gravitational interactions among these three bodies create a dynamic, nonlinear system where slight variations in initial conditions, for example, minor variations in the distances or velocities of any one body, can lead to vastly different outcomes; the long-term positions of the three bodies become practically impossible to predict.

In broader mathematical and scientific terms, ‘chaos’ refers to systems that appear random yet are inherently deterministic. Take the example of a roulette wheel, commonly perceived as a game of chance. While we might assume the outcome is purely random, the underlying mechanics of the roulette wheel, including the motion, friction and the force of the spin, adhere to deterministic physical laws. The true source of unpredictability stems from its extreme sensitivity to initial conditions: how forcefully the ball is dropped, the speed at which the wheel spins, subtle vibrations from environmental factors like an air conditioner, and even the movement of patrons around the table. These factors, often unnoticed, can significantly influence the outcome of each spin. Chaos theory teaches us that even seemingly insignificant variations in initial conditions – a fraction of a millimetre difference in the ball’s drop point – can lead to disproportionately large effects.

Colloquially known as the butterfly effect, chaos theory can shatter our common notion of cause and effect. It suggests that predicting the long-term future is incredibly complex because even tiny, seemingly irrelevant events can have significant consequences.

The term ‘butterfly effect’ is often attributed to the meteorologist Edward Lorenz, who used the now-familiar example to describe chaos: a butterfly flapping its wings in Brazil could set off a chain of events leading to a hurricane in Texas three weeks later.

This seemingly outlandish scenario underscores the counterintuitive nature of chaos theory. While the idea of small causes having large effects might feel familiar, chaos theory challenges our common assumptions about how the world works. The surprising lesson isn’t that small events can have significant consequences but, rather, the profound difficulty in predicting those consequences. This core principle – the difficulty in prediction – has a technical definition: ‘sensitive dependence’ on initial conditions – for instance, a roulette ball’s position before it is dropped, the speed of the roulette wheel, etc.

But sensitive dependence is not a novel concept. It has a place in history:

For want of a nail the shoe was lost.
For want of a shoe the horse was lost.
For want of a horse the rider was lost.
For want of a rider the battle was lost.
For want of a battle the kingdom was lost.
 
‘For want of a nail’ captures a familiar notion about causality – small events can cascade into significant consequences.

Yet, within the framework of chaos theory, we can take this idea further.

Consider the potential for sudden changes due to phase transitions, as when the swirling water goes from smooth to turbulent. Tiny variations in a system’s conditions, like a seemingly insignificant missing nail, can accumulate and trigger an unexpected shift – the shoe falling off, the horse being injured, the battle being lost. These sudden changes, surprising transitions within the system, are driven by underlying physical laws, yet they reveal the inherent unpredictability and complexity embedded in what might seem like straightforward events.

Just as a missing nail leads to the loss of a kingdom, could the flutter of a distant insect trigger catastrophic events? The answer, perhaps surprisingly, depends on perspective – how we choose to look at the world and how we understand cause and effect.

Before we consider the two distinct perspectives, it is critical to note that the butterfly effect is a metaphor for a theory, namely, chaos – the idea that small changes in conditions can have large, unexpected effects. While the butterfly effect is a powerful image, it’s important to remember the scientific foundation Lorenz’s work provided.

11 philosophers you don't know about, but should

Martha Nussbaum, Carlo Rovelli and other philosophers draw the short list.

IAI Editorial, 11/14/23

For World Philosophy Day 2023, eleven leading thinkers nominate philosophers you probably haven't heard of, but you should know about, from Ancient Greece all the way to the present day. Martha Nussbaum, Carlo Rovelli, Cheryl Misak, Peter Adamson, Andrew Bowie, Tommy J Curry, Emily Thomas, Paul Giladi, Maria Balaska, Sara Heinämaam, Hugo Drochon and Sophie-Grace Chappell put forward their choices.

Martha C. Nussbaum

Porphyry (c. 234 - c. 305 CE)

A Neoplatonic philosopher born in Tyre, and later living at Rome, who wrote in Greek.  He wrote the best work in the entire history of Western philosophy before the twentieth century on the intelligence and complex sentience of nonhuman animals and the cogent reasons for not killing and eating them. Called "On Abstaining from Eating Animals," it is a very lengthy work and survives in its entirety. An English translation by Gillian Clark was published in 2000 by Cornell University Press.

Martha C. Nussbaum is Distinguished Service Professor of Law and Ethics at the University of Chicago and one of the world’s most celebrated moral philosophers, according to the Financial Times.

Carlo Rovelli

Anaximander of Miletus, 5th century BCE

Anaximander is a giant of human thinking, standing at one of the deep roots of modernity and is very little known.  He is the one that realized the first cosmological revolution, understanding that the sky above us continues below us and the Earth is a big stone floating in the void.  This is the discovery of the worldview that will characterize the West for centuries, the birth of cosmology, and is the first scientific revolution. It is the discovery that scientific revolutions are possible: in order for us to understand the world, we must be aware that our current worldview may be mistaken, and we can redraw it.  He is the first geographer.: the first to draw geographical maps.  The first biologist, contemplating the possibility that living beings evolved over time. He is the first astronomer, making a rational study of the movements of heavenly bodies and seeking to reproduce them with a geometrical model. He is the first to propose two conceptual tools that would prove fundamental to scientific activity: the idea of natural law, guiding the unfolding of events over time and by necessity; and the use of theoretical terms to postulate new entities, hypostases used to make sense of the observable world. He starts the critical tradition that forms the basis of today’s scientific thinking: he follows his master Thales's path while at the same time searching for his master’s mistakes.  He created what the Greeks called Peri phuseos istoria (hence “physics”), the “inquiry into nature,” giving birth to a tradition that would form a deep root basis for the entire scientific development to come.  Even the literary form of this tradition, a treatise in prose, starts with him.

Carlo Rovelli is an Italian theoretical physicist and loop quantum gravity pioneer. He is the author of, many bestselling books, including The Order of Time, Reality Is Not What It Seems, and Anaximander.

Maria Balaska

Cora Diamond (1937 - )

Asking ‘What do women want in a moral theory?’, Annette Baier in 1985 included Cora Diamond in her list of women philosophers who spoke 'in a different voice from a standard moral philosopher's voice'. Since then many years have passed and Cora Diamond has been giving us more and more samples of that voice. At a time where so many philosophers still put forward a view of ethics as a series of calculations, mapped on endless versions of trolley problems, it is imperative that we listen to a voice that can teach us differences, as Wittgenstein had hoped for. From her early thought-provoking 'Eating Meat and Eating People' to her more recent discussions on the nature of truth in ethics (what should we make of the statement 'Slavery is wrong'?), Diamond keeps bringing philosophy face to face with what she calls 'difficulties of reality'. This is where philosophy begins.

Maria Balaska is a research fellow at the University of Hertfordshire and at Åbo Akademi University. She is the author of Wittgenstein and Lacan at the limit: meaning, and astonishment, and the editor of Cora Diamond on Ethics.

Peter Adamson

Fakhr al-Din al-Razi (1150 - 1210 CE)

A formidable theologian and philosopher who responded in great detail to the ideas of the more famous Ibn Sina (Avicenna, who died in 1037). Al-Razi is well known in the Islamic world as the author of a massive commentary on the Quran but also wrote many works detailing his disagreements, and occasional agreements, with Ibn Sina. He had innovative things to say on pretty much every area of philosophy, for instance by challenging Ibn Sinā on points of logic, developing a new conception of metaphysics, and arguing for a consequentialist ethics. It's especially interesting to see how he weaves together ideas from Avicennan philosophy with doctrines from Islamic theology. He was also very influential, and was quoted for centuries in later Islamic philosophy.

Peter Adamson is Professor of Ancient and Medieval Philosophy at King’s College London, and Professor of Philosophy in Late Antiquity and the Islamic World at Ludwig Maximilan University of Munich. He is the host of the podcast History of Philosophy Without Any Gaps.

 Cheryl Misak

Frank Ramsey (1903 – 1930)

Frank Ramsey died at the age of 26, too young to have personally influenced generations of students. But his importance is legendary. He was at least Wittgenstein’s equal in philosophy and a major influence on his difficult friend. In philosophy, we have Ramsey Sentences, Ramsey Conditionalization, and much more. A fruitful branch of combinatoric mathematics is named after him. He founded two branches of economics and, in figuring out how to measure degrees of belief, laid the basis for contemporary economics and social science.

His life was as exciting. He began his Cambridge undergraduate degree just as the Great War was ending; he was part of the race to be psychoanalyzed by Freudians in Vienna; and he was in with the Bloomsbury set of writers and artists. Virginia Woolf described him ‘as something like a Darwin, broad, thick, powerful, & a great mathematician, & clumsy to boot.’ As if that weren’t enough, he had important things to say about (socialist) politics and the (atheist) meaning of life.

Cheryl Misak is University Professor and Professor of Philosophy, University of Toronto, and author of, among other books, Frank Ramsey: A Sheer Excess of Powers.

Andrew Bowie

Friedrich Daniel Ernst Schleiermacher (1768 - 1834)

Schleiermacher is well known as a key founder of modern Protestant theology, but in the Anglophone world he is still not widely known for his philosophical insights into language, that presage key ideas present in Wittgenstein, Habermas, Brandom, and others, let alone his views on aesthetics, and ethics. These ideas emerge particularly through his concern with interpretation as fundamental to human existence. He sees interpretation as an ‘art’, which is ‘that for which there admittedly are rules, but the combinatory application of these rules cannot in turn be rule-bound’. This leads him to a rejection of foundational forms of epistemology: the ‘completion’ of episteme is ‘coming to an understanding’, which is ‘an art techne’. It is ‘an activity’ and episteme and techne ‘are the same’. As such, ‘the art of finding principles of knowledge can be none other than our art of carrying on conversation’. This leads him to a rejection of the analytic/synthetic distinction: the ‘difference therefore just expresses a different state of the formation of concepts’. By taking issues present in aesthetics as central to philosophy he offers an alternative approach to modern philosophy which has not been adequately appreciated.

Andrew Bowie is Emeritus Professor of Philosophy and German at Royal Holloway, university of London, and author of, most recently, Aesthetic Dimensions of Modern Philosophy.

Tommy J. Curry

Jean-Louis Vastey (1781 - 1820)

Also known as Pompée Valetin, Baron de Vastey, he authored The Colonial System Unveiled in 1814. This book analysed the colonial endeavours of Europe broadly as a system of ideological claims driven by greed. Vastey explained: “When Europeans came to the new world, their first steps were accompanied by crimes on a grand scale, massacres, the destruction of empires, the obliteration of entire nations from the ranks of the living”. Baron de Vastey argued that Europe’s economic and intellectual advances were not based on its superior white civilization but on its unbridled genocide and violence against darker races. Baron de Vastey claimed that Europe’s Enlightenment was rooted in racist pseudo-sciences dedicated to advancing slavery and colonialism against the humanity of African and Indigenous peoples and greed, not knowledge.  

Baron de Vastey’s philosophy explored topics of historiography, ethnology, and Black self-determination that laid the foundation of normative Black political theory and decolonial ethics well into the early 20^th century. 

Tommy J. Curry is an American scholar, author and professor of philosophy, holding a Personal Chair in Africana philosophy and Black male studies at the University of Edinburgh. He is the author, most recently, of Another White Man's Burden: Josiah Royce's Quest for a Philosophy of White Racial Empire.

Emily Thomas

Constance Naden (1858 – 1889)

Constance Naden is well-known as a Victorian poet, but she was also a philosopher. During the 1880s, she drew on the science of her day to controversially defend atheism and materialism. I read Naden as arguing that, whilst we only directly know the contents of our own minds, we should believe that outside our minds lies matter. And, as neuroscience shows our brains deeply affect our minds, we should believe our minds are made of matter. To give a flavour of Naden’s work, take her 1882 “Animal Automatism”. It attacks evolutionist T. H. Huxley for advocating a kind of ‘phenomenalism’, on which matter depends for its existence on our minds. Against this, Naden turns Huxley’s own evolutionary theories against him. “Unless his views have recently undergone a marvellous change,” Naden writes, “the earth was in being very long before the appearance of any sentient organism”, and “mind is developed from matter”. Mind, indeed life itself, evolved in the distant past from non-living matter. So matter must exist independently of us.

Emily Thomas is Professor of Philosophy at the University of Durham, and author, most recently, of a book on Victoria Welby.

Paul Giladi

Enrique Dussel (1934 - 2023)

Dussel was arguably the most important philosopher from South America born in the 20th century. Though rarely (if at all) featured and discussed in mainstream Anglo-American and continental European philosophical circles, he was a prolific writer and world-leading figure in the articulation and propagation of liberation theology.

Dussel is also known for developing the radical and challenging concept of ‘transmodernity’. Throughout his life’s work on this difficult subject, Dussel argued that transmodernity is a way of producing both a lifeworld (a set of values that are formative for developing society, personality, and culture) and economic systems that transcend the Global North-centric conflict between modernity and postmodernity. Transmodern thinking and institutional design operate under an ‘ana-dialectic’ or ‘analectic’ logic, which moves critical theory and political economy beyond the Frankfurt School and Foucault, and instead centres the voices, epistemologies, and vocabularies of ideologically-marginalised Global South communities.

Dussel famously wrote that a “project of ‘trans’-modernity, a ‘beyond’ that transcends Western modernity (since the West has never adopted it but, rather, has scorned it and valued it as “nothing”) … will have a creative function of great significance in the twenty-first century”. Given how the Global South is currently posing concrete challenges to the Global North’s hegemony, Frantz Fanon’s vision of a ‘critical humanism’ produced by the Global South may start to materialise in no small part due to Dussel’s work.

Paul Giladi is a university lecturer in philosophy at the School for Oriental and African Studies, co-founder of the Naturalism, Modernity, Civilization and International Research Network. He is the co-editor of Epistemic Injustice and the Philosophy of Recognition.

Sara Heinämaa

Aurel Kolnai (1900 - 1973)

Aurel Kolnai’s phenomenology of disgust is still the best philosophical analysis of the emotion that we have. Via various readings, it influenced many 20th century theories of revulsion and nausea, but also ingenious artistic presentations of the emotion in paining and cinema. Most importantly Salvador Dali and, via Dali, also Alfred Hitchcock, drew from Kolnai’s insights. Similarly Kolnai’s analysis of game-behavior still operates as a secret source of many 21st century contributions in philosophy of games. Its distinctions help us understand what is at issue in ice hockey and boxing but also in virtual games, war games and chess. Finally, Kolnai’s early analysis of Nazism, The War Against the West (1938), illuminates new totalitarian ideologies that are mushrooming in our own time. The unifying topic of all Kolnai’s contributions is the question how willing and feeling combine in human behavior. We would do well if we were to attend to his alert.

Sara Heinämaa is Professor of Philosophy, University of University of Jyväskylä and President of the Philosophical Society of Finland. She is the author of Toward A Phenomenology of Sexual Difference.

Hugo Druchon

Vilfredo Pareto (1848 - 1923)

Italian economist, sociologist, and philosopher, Pareto is perhaps best known for 80/20 rule - the thesis that 80% of wealth will always belong to 20% of the population, in an early rending of the 1% vs the 99%. He is worth revisiting today to help us understand the political era of populism we are still in the midst of.  Populism pits a pure people against a corrupt elite. Yet most populist leaders are themselves elites. Trump is part of the financial 1% and was a TV star (The Apprentice) before coming to the White House. Boris Johnson is as establishment as they get: Eton, Oxford. Here, Pareto’s ‘circulation of elites’ thesis can come in handy. Pareto saw politics as the competition between ‘lions’ and ‘foxes’ (both expressions of the elite): lions more inclined towards centralised and faith-based rule, foxes in support of decentralisation and scepticism. Maybe another way to interpret the politics of the last while is to think of it as a circulation from foxes to lions? 

Hugo Drochon is Associate Professor of Political Theory at the University of Nottingham, and author of the book Nietzsche's Great Politics.

Sophie-Grace Chappell

Aurel Kolnai (1900 - 1973)

I don’t know if people haven’t heard of Aurel Kolnai (1900-1973)—perhaps they have—but he is certainly someone whose work deserves more attention. He was an ethical philosopher who began with experience, not with systematic theories or grands récits, and whose influences included Aquinas, Husserl, G.K.Chesterton, Scheler, and British “common sense” philosophy. He himself was an influence on Bernard Williams, David Wiggins, Isaiah Berlin, and Vaclav Havel. As someone outside the “analytic mainstream”, and as a Jewish Catholic philosopher from Austria-Hungary in the time of the Nazis, he had great difficulty throughout his life in securing a conventional job in academic philosophy. But his writings, with their scepticism both about totalitarianism in politics and about what Levinas calls totalisation in philosophy, are of permanent value—and given that he wrote an anti-Nazi reflection with the title The War Against The West, perhaps have a particular resonance at our present unfortunate point in history.

Sophie-Grace Chappell is a Professor of Philosophy at the Open University, who writes about ethics, politics, feminism and epistemology. Her books include Ethics Beyond the Limits, Knowing What To Do, and Ethics and Experience. Her most recent book is the edited collection Intuition, Theory, and Anti-Theory in Ethics, published in 2015.

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7 philosophy books that shaped Western thought

Dive into seven texts that continue to shape Western philosophy, from ancient Mesopotamia to Greece's brightest minds.

Scotty Hendricks, 09/11/23

KEY TAKEAWAYS

*  These seven philosophical texts have shaped the contours of Western thought, delving into questions of justice, existence, and human nature. 
*  While celebrated works such as Plato's Republic offer insights into justice and reality, lesser-known pieces like the Mesopotamian Dialogue of Pessimism illuminate ancient perspectives on life's absurdities. 
*  Collectively, these writings underscore the rich tapestry of ideas that have laid the foundation for contemporary philosophical discourse.

Books possess a unique magic: With only ink and paper, they can communicate thoughts from a person who is separated from you by thousands of years and unfathomable cultural space. For some particularly original thinkers, this has allowed mere fragments of text to influence the course of human thought for thousands of years. The following seven influential philosophy books have helped shape the intellectual history of the Western world and, more recently, the entire planet.

Dialogue of Pessimism — Unknown author

Ancient Greece is the culture most associated with philosophy. However, it is wrong to think that nobody else studied it. Plato himself wrote about Egypt’s long philosophical history, for example. Unfortunately, however, there is precious little surviving philosophy that originated across the rest of the Mediterranean and Mesopotamian worlds. 

One of the surviving texts is the Dialogue of Pessimism. It exists in two similar forms: one Assyrian and one Babylonian. While parts of both are fragmentary, it is the best-preserved example of Mesopotamian “wisdom texts.” Framed as a dialogue between two characters, an Aristocrat and his Slave, the text consists of the Aristocrat proposing ideas for things to do to the Slave, who provides good reasons for them. The Aristocrat then proposes opposing ideas, yet the Slave is just as easily able to defend those. The last few lines reflect on the absurdity of life. Many interpretations of this exist. Some suggest it is a precursor to modern existentialist thought, particularly that of Camus or Søren Kierkegaard. It is easy to see that from the final lines of the text:

“Slave, listen to me!
Here I am, master, here I am! 
What then is good? To have my neck and yours broken, or to be thrown into the river, is that good? 
Who is so tall as to ascend to heaven? Who is so broad as to encompass the entire world? 
 O well, slave! I will kill you and send you first! 
 Yes, but my master would certainly not survive me for three days!”

Babylonian thought is so foundational that its influence is often overlooked. We still use Babylonian units to measure time. Their astronomers laid the foundations for both modern astronomy and science itself. And it is speculated that many Greek thinkers, such as Thales, were influenced by Babylonian thought. The Dialogue of Pessimism is thought to have influenced biblical texts, particularly Ecclesiastes, and can be viewed as a forerunner of Plato’s Socratic Dialogues.

Poems — Xenophanes

The first pre-Socratic philosopher with a considerable amount of extant writing samples for us to review is Xenophanes. Unlike many of his contemporaries, he wrote many different books and poems. Enough fragments of his work survive to give us something beyond later commentary. While a full picture of his thoughts is impossible to form, what does exist demonstrates why he was one of the most influential pre-Socratic philosophers. 

Xenophanes is principally known for his theology. He argued that common conceptions about the gods in the Greek world were mistaken. His view of God was spherical: lacking human traits, and perhaps directly identifiable with the Universe. While there is some debate around his exact wording, he may have been the first Western monotheist, or arguably even pantheist. He mused that humans tended to give their gods familiar traits:

“Thracians that theirs are blue-eyed and red-haired. But if horses or oxen or lions had hands or could draw with their hands and accomplish such works as men, horses would draw the figures of the gods as similar to horses, and the oxen as similar to oxen, and they would make the bodies of the sort which each of them had.”

His principal philosophical legacy lies in his approach to epistemology and skepticism. While he argued for the existence of objective truths, he doubted the ability of humans to ascertain them. He noted that our beliefs were limited by our knowledge and used this as evidence for how little we can truly know:

“If god had not made yellow honey [we] would think that figs were much sweeter.”

The skeptics of the ancient world would claim him as a critical influence. However, recent interpretations lean toward Xenophanes’ warning against dogmatic approaches or claims to certainty rather than a hard-line skeptic position. In either case, his writings are among the first to consider the problem of how we can claim to know anything — a problem people still grapple with today. 

On Nature — Parmenides

Parmenides is one of the most important ancient philosophers you’ve never heard about. Working in Elea, a Greek colony in what is now southern Italy, he wrote a single book that exists only in fragmented quotations and later authors’ commentaries. Through these, he has impacted virtually all subsequent Western philosophy. 

While the name was probably a later invention — On Nature was a commonly applied name for works describing the Universe — Parmenides’ poem is one of the most important texts in Greek philosophy. In it, he invented metaphysics and contributed to logic by laying out his arguments with deductive rigor. Unlike his predecessors — famed for arguing that the world was made of a single, physical element — Parmenides argued that the world is a single, unchanging substance and that our notions of motion, change, creation, and destruction are all mistaken. The world we interact with is not the “true” reality but only a set of appearances. He also maintains that empty space is impossible since the idea of “nothing” is contradictory. 

 In his words:

“…the only routes of inquiry that are for thinking: the one, that it is and that it is not possible for it not to be, is the path of Persuasion (for it attends upon Truth), the other, that it is not and that it is right that it not be, this indeed I declare to you to be a path entirely unable to be investigated: For neither can you know what is not (for it is not to be accomplished) nor can you declare it. For the same thing is for thinking and for being.”

Parmenides’ legacy is vast. His work directly influenced Plato, who argued that the world we engage with is a mere copy of the world of “forms.” Through Plato, Parmenides impacted nearly all of subsequent Western philosophy. His ideas on time and space continue to influence modern debates. 

Discourses of Epictetus — Flavius Arrian 

Epictetus was a Stoic philosopher in the Roman Empire during the second century. Born in what is now Turkey, he was enslaved and owned by Emperor Nero’s secretary at one point. While in servitude, he began receiving an education in Stoic philosophy from Musonius Rufus. After his freedom was restored, he was banished to Greece, where he founded a well-regarded school. Known for teaching Stoicism as a way of life rather than just a pure philosophy, he was well-known in his day — some sources suggest he was more famous than Plato was during his lifetime. 

Discourses is a series of polished notes from post-lecture discussions. It was likely written by his student, Flavius Arrian. While the exact length of the original text remains unknown, some sources suggest there were eight books in the complete set. Today we have four. These cover a wide range of topics relatable to anyone at any time and present Stoicism as a guide to life rather than a dry philosophy. One of the more famous quotes expresses why a person should bother to study at all:

“For on these matters we should not trust the multitude who say that none ought to be educated but the free, but rather to philosophers, who say that the educated alone are free.”

Discourses is one of the earliest records we have of the thoughts of a Stoic thinker. Marcus Aurelius held it in high regard and quoted it in Meditations. It was also the source for The Handbook, an introduction to Stoic philosophy aimed at popular audiences, also likely penned by Arrian. This book has proven popular, especially during increases in the popularity of Stoic thought.

Republic — Plato

Plato’s Republic is arguably one of the most famous works in philosophy. Framed as a discussion between Socrates and several others about the nature of justice, it provides us with some of the most enduring philosophical arguments and images. 

Socrates addresses the idea of justice by analogy, using the concept of a “just city” to understand how justice impacts the soul. His perfect city has attracted a great deal of attention over the millennia. Along the way, he considers how acquiring knowledge is like leaving a dark cave, what exactly love is, the differences between reality and the world we engage with, and what would happen if you gave a man a magic ring that turned him invisible. 

Many lines from Republic have become widely known. One particularly famous example is: