Discussion about Graham Priest's dialetheic views on Eastern and Western philosophy

Question

Australian philosopher Graham Priest is famous for advocating Dialetheism, the view that there are true contradictions. Dialetheism goes against the law of non-contradiction. This gives rise to the non classical logical systems which had much bigger popularity in India. One of them is known as catuṣkoṭi (lat. tetralemma). Tetralemma allows the statement to be true, false, both or neither. "Tetra" comes from these four options.

Classical Aristotelian logic claims that it is impossible for the latter two options to be true. This is expressed as law of non-contradiction (statement can't be both true and false) and law of excluded middle (statement is either true or false). Both are the essence of classical logic which heavily influenced Western philosophy. Kant, Wittgenstein and Heidegger all claimed to come towards contradictions in their work and all thought that their ideas hence must be incorrect or incoherent. While I'm not sure whether dialetheism holds a solution in their case, I'd like to refer to the case where I think it does hold. Namely, Mahāyāna Buddhism.

I agree with G. Priest that classical logic has its limits. It can't give answers to some philosophical questions.

Tetralemma is more encompassing logical system which can deal with questions classical logic can't. To draw the parallel with physics, classical logic bears the similar relationship to tetralemma as Newtonian theory of gravity bears towards the general theory of relativity.

I'd like to continue this discussion in the context of Mahāyāna Buddhism and how it relates to dialetheism.

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One of the most important teachings in Mahāyāna is śūnyatā, (engl. emptiness). Emptiness is a metaphysical claim that phenomena lack real and substantial existence. They lack any nature by themselves and derive their identity by how they relate to other things. Their existence is only relative. Emptiness is thus tightly connected to another essential teaching in Buddhism, dependent origination (Sanskrit. Pratītyasamutpāda).

Nāgārjuna was a Buddhist philosopher who defended emptiness against some other philosophical schools in ancient India (Nyāya and Vaisheshika) and some interpretations of dharma (Buddhist thought) which saw some phenomena as having real existence. His claim is that everything is empty including emptiness. This means that everything is dependently originated.

In Sangha (Buddhist community), one can often hear statements that ultimate reality is beyond concepts and can't be talked about. Definition of ultimate reality is given as a reality realised when all concepts are removed through the teaching of emptiness. The previous sentence is a statement that I'll argue is a true contradiction.

One can argue that the previous statement is false by pointing out that saying "something is beyond concepts" is itself a concept. If something is truly beyond concepts, we couldn't talk about it at all, and neither could we give any statements about it. This must include even saying that it's beyond concepts. However, the statement can be also regarded as true in the sense that we can't really say much about ultimate reality except that it's beyond concepts and descriptions. We need to let go of concepts to enter the ultimate:

• In the case when the statement is verified as false, we're defining "ability to talk about ultimate reality" as an "ability to give any statements about it".

• In the case when the statement is verified as true, we're defining "ability to talk about ultimate reality" as an "ability to give some statements about it (however limited they are)".

Therefore, the truth value of the statement depends on how "ability to talk about ultimate reality" is defined.

From the above arguments, we can conclude that ultimate reality can be talked about, in a limited way.

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However, if we get back to the definition of the ultimate reality as "non-conceptual reality that is realised through emptiness", we have a problem. If we can talk about it, even in a limited way, we're still applying concepts to a reality that's non-conceptual by definition. We again come to the contradiction. How do we solve this? Kant, Heidegger and Wittgenstein didn't know.

Wittgenstein claims in the end of Tractatus that his work is meaningless as he gave statements about things he claimed can't be done. I'm not sure whether dialethism is really a solution in the case of Wittgenstein, but if one does agree with him, one is facing a contradiction. He concluded thus that Tractatus is meaningless.

I'll argue that this a bad move.

If Tractatus really were meaningless, than it can't establish anything and hence motivate the view that you can't give statements about some things (form, in his case). It's shooting oneself in the foot as Wittgeinstein's conclusion undermines the very idea he tries to make (that there are things one can't make statements about). In another words, if Tractatus is meaningless than Wittgenstein has no grounds to support his claim that statements can't be given about form.

Hence, if Tractatus were truly meaningless then it cannot motivate the view that it's meaningless.

This example shows how trying to avoid contradiction leads to incoherent conclusions.

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Catuṣkoṭi provides a compelling, but counter-intuitive alternative, just accept contradiction. Some statements can be both true and false in the same sense.

Nāgārjuna used Catuṣkoṭi in his work which explains why he had much less problems with contradictions.

We conclude that "Ultimate reality is non-conceptual reality that's realised through emptiness" is a dialetheia, a true contradiction.

Nāgārjuna argued the same and came to the same conclusion.

My question: For people who are familiar with Graham Priest and his work, how do you see his views on Dialetheism?

Answer 1

Honestly, his entire point is that the liar paradox is both true and false; ergo, the Law of noncontradiction is bad! This just shows that he misunderstand the liar paradox completely. Please refer to the Wikipedia article Liar paradox where you can find actual solutions to this. Thus, we don't have to bite the bullet on "there are true contradictions in the world".

When you say "I agree with G. Priest that classical logic has its limits. It can't give answers to some philosophical questions", can you name a philosophical question that the Law of noncontradiction (LNC) cannot address?

Answer 2

OP: We conclude that "Ultimate reality is non-conceptual reality that's realised through emptiness" is a dialethia, a true contradiction.

Ultimate reality. Is this where Descartes' cogito comes from? or is this the reality beyond appearance, the thing-in-itself?

OP: Emptiness is a metaphysical claim that phenomena lack real and substantial existence.

The phenomena are mind-dependent appearances of things-in-themselves, of which the latter we know nothing. They are to us as nothing, so the phenomena are empty.

It is like the city of the Gandharvas which the unwitting take to be a real city though it is not so in fact. The city appears as in a vision owing to their attachment to the memory of a city preserved in the mind as a seed; the city can thus be said to be both existent and non-existent. (Lankavatara Sutra)

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To the extent that physics studies the observable it therefore deals with phenomenal nature, while the unobserved is noumenal nature, of which we know nothing.

Perhaps Descartes' cogito could be considered to come from nature, but this might be an assertion too far for Heidegger. Insofar as the cogito is a type of Being ...

Being and the structure of Being lie beyond every entity and every possible character which an entity may possess. (GA 2, H. 38, 1927)

So we can say very little about being. In fact we are back to nothing again, rather like another noumenon.

The nothing is the "not" of beings, and is thus being, experienced from the perspective of beings. (1949 preface to On the Essence of Ground, Pathmarks, p. 97)

This does not seem to be a dialethic contradiction. Just a consequence of perspectives.

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OP: If we can talk about it, even in a limited way, we're still applying concepts to a reality that's non-conceptual by definition.

Seems rather like talking about a concept that is indefinable.

It has been maintained secondly that the concept of 'Being' is indefinable. (GA 2, H. 4)

But that is not a contradition either.

Answer 3

The clear answer is that the ultimate reality isnt beyond concepts, and the definition simply doesnt hold. Ultimately Priest and all dialetheists have a serious semantical problem in their hands, which is the problem of destroying the sense of negation. Namely, contradictions by definition cannot be true since contradictions are basically conjunctions of contradictory terms, and contradictory terms are literally defined as terms which cant be both true (nor both false), which ironically entails that dialetheism actually supports the law of non-contradiction. However, as one can obviously know, dialetheism also opposes the law of non-contradiction. So what is the solution? It's simple: it is just one more contradiction for the dialetheist that the LNC and dialetheism both hold. And this "solution" makes dialetheism nonsensical, as even its negation properly loses the sense of a negation. This is the problem pointed out by Arenhart in his critique of the dialetheist solution to the liar paradox. About catuskoti, i feel like denying the law of excluded-middle should really make catuskoti just an arbitrary limitation. P is both true and false, or true and only true, or false and only false, or neither true nor false. Why not posit that P is not neither true nor false nor both true and false, nor true and only true or false and only false? If truth and falsity arent the only options then catuskoti (like literally any attempt to pinpoint truth values) is absurd and simply too limited. Either u accept that truth and falsity are exhaustive or u will have to deny any attempt to pinpoint truth values.