Contextual dyadic thinking is proposed by Keekok Lee in her 2017 The Philosophical Foundations of Classical Chinese Medicine. This is a way of appreciating Chinese implicit logic, as an alternative to dualistic thinking that has developed over centuries in Western philosophy.
Chapter 9: Modes of Thinking
Chinese philosophy did/does not appear to have a branch designated “Logic” in the way that such a subject exists in Western philosophy as formal logic. 
-  This could be regarded as controversial, but for a reason which will soon become obvious, this author chooses to follow Kurtz, 2011 which gives a detailed discussion of the search among Chinese scholars during the last hundred years or so for fragments of texts which could be used to support the claim that Chinese philosophy or must have developed logic in the European understanding of that term as formal logic. The operative phrase is “the European understanding of that term as formal logic.” as it is clear that (ancient) Chinese philosophers had an interest in logic—it was just that their pre-occupation with it was not expressed in the same way as European philosophers (since ancient Greek philosophy) had/have pursued the subject as formal logic.
However, although it is undoubtedly true that Chinese philosophy did not engage with formal logic, it may be precipitous to dismiss the notion of logic (short of formal logic) as irrelevant to the various Chinese modes of thinking. This chapter will explore the cluster of related themes listed below:
1. Why did the Chinese not engage with formal logic? The Contextual mode of thinking is key to understanding how their philosophy and world-view were shaped.
2. The distinction between dyadism and dualism: the Chinese mode of thinking is dyadic, not dualistic as modem Western philosophy is.
3. The ancient Chinese operated with an implicit logic, which may be called Yinyang/Yao-gua logic.
4. Two-valued and many-valued logic; classical logic in the West is two-valued, while it could be argued that embedded in Yinyang/Yao-gua metaphysics and its model of thinking is an implicit logic which is many-valued.
The latter two points extend into “implicit logic“. For these excerpts, let’s focus on (1) the contextual mode of thinking; and (2) dyadism and dualism.
It is not an exaggeration to say that contextual thinking  was/is truly foundational to Chinese thought, laying down the framework in which Yinyang/Yao-gua thinking and what this author calls Yinyang/Yao-gua implicit logic were to be understood. So what is contextual thinking in the ancient Chinese context?
-  This author can track down one work (in English), written by the psychologist, Nisbett, 2003/2005: xix which raises this matter, claiming that even today, those brought up in and influenced historically by Chinese culture are “better able to see relationships among events than Westerners …”, why Westerners are “so likely to overlook the influence of context on the behaviour of objects and even of people”
Let’s skip past the deep reading in The Zhuangzi, forward a few pages.
The Contextual Mode in general amounts to this: the two values, truth and falsity, have no proper application in the abstract or vacuum — they only have application and meaning relative to a particular context, They are context-bound. The two instances of female beauty cited above make clear this point—they embodied beauty in the human context. If the beholder were not a human, but a fish, a bird, or a deer, they would even be repelled by such a sight which would inspire in them fear and flight. It makes no sense to discuss beauty or ugliness (truth or falsity) in a vacuum, free of a particular context. These values, even in a human context, would not necessarily yield fruitful discussion unless the disputants are fully aware of the context in which the claim of beauty, say, is made, and when the contexts are made clear, the dispute would lose purchase as each side would have realized that it would be futile to continue to maintain that only one’s own candidate for beauty/truth/falsity constitutes the winner, while rival claims are the losers. For instance, the paradigm of female beauty in the Tang was very different from that of the Song Dynasty just as the paradigm of female beauty today in the modem world (as displayed by models along the catwalk) is very different from that of the Renaissance period in European history.
Focusing on context renders the respective criteria or standards used by the disputants in contesting their case visible and obvious. These criteria may be incommensurable—if the most significant criterion for determining female beauty is to be thin as a rake for Party A but to be as amply endowed as a Tang or Renaissance lady for Party B, then it becomes obvious that argument is fruitless. Of course, this is not to say that all disputes entail incommensurable criteria or standards.  Whether a dispute does or not itself involve incommensurability depends on the context of the dispute—this is indeed the key thing to grasp about the Contextual Mode of Thinking.
-  For instance, scientfic disputes are not necessarily subject to incommensurabilty, contrary to what some Kuhnians might wish to claim— see Lee, 1984 [i.e. difficult to find journal, ‘Kuhn – A Re-appraisal’ in Explorations in Knowledge, 1984, pp33-88.]
In turn what is the key implication of the Contextual Mode? It is this: its incompatibility with formal logic, whether as traditional syllogistic logic or as modem propositional logic since the twentieth century, as the latter implies the intelligibility of studying relations between assertions looked at solely through their formal relations as extreme abstractions, with no reference either to content or to context.  In contrast, in evaluating an argument, the ancient Chinese were interested not merely in the concept of validity but also in the truth of what was said. For them, as the passages from the Zhuangzi make clear, they held that truth depended on context, that truth could not be understood in abstraction or extrapolation from the context in which the assertion is embedded. Hence from the standpoint of the Contextual Mode, a project such as formal logic would be absurd, impossible, fruitless, and pointless. Hence the ancient Chinese had steered clear of it. This is the most important conclusion to draw from the brief discussion here of the Contextual Mode of Thinking as the over-arching mode in ancient Chinese thinking. The next section deals with an embellishment of this fundamental mode of thinking, marrying it to dyadic as opposed to dualistic thinking. The section, which follows it, will then explore more fully the implications of what this author calls the Contextual-dyadic Mode for logic in Chinese philosophy.
-  One particular example of the presentation of syllogistic logic in an introductory text of the discipline would look like this: All Ms are Ps; S is M, therefore, S is P. This argument is valid because it satisfies the rule that the middle term (M) is distributed. One does not need to know what the terms, M, P, and S stand for or refer to, as formal logic is not interested per se in truth, but only in validity.
That covers context. However, in order to appreciate dyadic thinking, we first need to understand dualistic thinking.
To put things baldly, ancient/traditional Chinese thinking is dyadic whereas European/Western/modern thinking is dualistic. Unfortunately, the distinction cannot be spelled out in a sentence or two right at the beginning of this exploration, but suffice it to say here that both forms of thinking deal with terms which constitute polar contrasts but which each respectively understands in very different ways.
We start first exploring dualistic thinking. It generally means that in any particular domain, there are two fundamentally different Kinds of things, categories or principles. For instance, in many forms of theology, such as Christianity, there are two basic entities, God and the Devil or God and human beings. In philosophy, ever since Descartes, a human being is said to be constituted of two entities — or substances, mind/soul and body. In biology/sociology/psychology/anthropology, human beings are divided into male and female. In geo-politics, humans are divided into White (European) and non-White (non-European). In environmental philosophy which deals with the relationship between Man and Nature, there is the culture (human) and nature (non-human) divide)
|God (Optional for Secularism
|Level 1||Nature (h)||Nature (nh)|
Lower animals and plants
|Level 4||Man||Woman||Subject-of-a-life /
capable of suffering
not capable of suffering
A slightly more elaborate schema is shown below about dualistic thinking.
In the table above:
|Nature (c)||Nature in the cosmological sense — the universe came into existence after the Big Bang and what has evolved since the Big Bang|
|Nature (h)||That part of Nature which refers to humans and their unique type of consciousness; it is also referred to as Culture (that is, human culture and civilization)|
|Nature (nh)||That part of Nature which is excluded by Nature (h) or Culture|
|Subject-of-a-life||Higher animals, in particular mammals, such as chimpanzees, lions, elephants. Such animals, although they do not possess the kind of sophisticated language humans possess which makes possible abstract thinking, are held, nonetheless, to have memories, capable of forward planning (in a non-linguistic manner), in some cases are said even to possess a sense of self|
|Capable of suffering||Animals which though not capable of what chimpanzees and elephants can do, nevertheless, are like them (and like humans) sentient and hence are capable of feeling pain. The lower animals and plants, however, are not capable of suffering pain as they lack the kind of nervous system possessed by humans and the higher animals, and hence are Non-subject-of-a-life|
These which can be inferred from the above representation of dualistic thinking are:
1. What is to the right and inferior and subordinate to what is on the left of each level; what is to the right is inferior and subordinate to what is on the left within each subdivision at each level.
2. Each level is subordinate to the level above it, such that ultimately all levels are subordinate to God in the religious/Christian version, although in the secular version, God drops out of the scheme.
3. What is on the right at each level (and each subdivision at each level) either has less or no value in themselves (no intrinsic value).
4. The religious as well as the secular versions are both compatible with extreme anthropocentricism (the view that only humans have intrinsic value and non-humans only have instrumental value for humans (see Lee, 1999, for details).
5.. In other words, 1 through 4 above imply that dualistic thinking is hierarchical thinking. As such, it is ideological thinking writ large, either designed intentionally or co- opted wittingly/unwittingly to entrench a political (in the wider sense of the term) order, celebrating unequal power relationships. In such pairings, the higher/superior class denigrates the “Other;” the two categories are not purely factual or empirical in character, but are heavily impregnated with moral/social meaning and significance. For instance, the human male is not simply a human being born with a certain kind of reproductive organ system, just as the female is not simply a human being born with a different kind of reproductive organ system.
6. It is Reductionist thinking—the inferior member of the pair is but an appendage, a mere shadow of the superior member. In the case of humans, the latter enjoys the status of being the epistemological/methodological authority, laying down criteria for what constitutes a “proper”/“good” specimen of the former.  Feminism complains bitterly on these two fronts. Historically, in the Mind/Soul and Body pairing, the former was privileged this held true in Christian theology; in Descartes’s view, this remained true, thereby releasing the Body as inert matter, fit for scientific investigation while retaining the Soul/Mind for higher things beyond, thereby escaping empirical/scientific probing. However, after Descartes, Materialism as the new metaphysics began to undermine this version of the Cartesian accommodation, turning the relationship upside down, with Body as Matter becoming the superior category while Mind was/is to be reduced to Matter. In Modern Medicine/Biomedicine, the human being is even conceived as machine, as artefact, no longer a naturally-occurring organism.  Dualism in this sense is the rival of Monism which may take the form of either Materialism (when Mind is reduced to Body) or Idealism (Body/Matter is reduced to Mind).
-  For a powerful account of dualism from the standpoint of feminism, see Plumwood, 1993 of which more would be said later.
-  On this ontological volte -face, see Lee, 2012b.
7. It is embedded within the framework of entity or thing- ontology. In chapter 8, the term “thing-ontology” is used as the context there makes it appropriate to do so. However, in this section, it may be more appropriate to use the term “entity ontology,” as God/Devil, Mind/Soul are not physical things but non-physical entities. (In other words, the class of entities is larger than that of things, as things— physical objects— are a special sub-set of entities.)
With this criticism of dualistic thinking, Lee proceeds to describe dyadic thinking, with the background of contextual thinking.
Contextual-dyadic Thinking: The Fuxi-Niiwa Myth
The term, “dyadism”/“dyadic thinking,” is only used in the sense which can be found in Lee, 1999 and used in opposition to those of dualistic thinking summarised in the section above, and should not be confused with other usages of the term by other writers. Lee, 1999 has introduced it specifically to oppose it to dualism, especially in the context of environmental philosophy and the philosophy of technology in the pairings of Human and Non- human as well as in the pairing of Culture (human) and Nature (non-human). Lee, 1999, 2006, 2012b in common with other critics of dualism, reject theses 1 and 2 set out above, while holding the denial of them to be constitutive of dyadism/dyadic thinking. It is time to spell out what it amounts to in the context of Chinese modes of thinking:
1. Dyadism, here, should be understood and discussed within the over-arching framework called Contextual Thinking. As Contextual Thinking is much more fundamental than even complementarity (of polar terms) in Chinese culture and civilization, let us call it Contextual- dyadic Thinking. 
-  For a like-minded account, see *Zhang, 2008 . [Editorial note, this cited book is written in the Chinese language. There’s an English language review: Wang, Robin R. 2009. “Zhang, Zailin 張再林, Traditional Chinese Philosophy as the Philosophy of the Body 作爲身體哲學的中國古代哲學.” Dao 8 (1): 113–16. https://doi.org/10.1007/s11712-008-9095-4.]
2. In dyadic thinking, strictly speaking, a term presupposes its opposite. For instance, “cat” implies the class of “non- cat.” An oppositional pair may then be drawn out, namely, cat and non-cat.
3. However, in the real world beyond that of strict logic, the class of non-cat is a very large class indeed, as it includes dogs, buttercups, humans, indeed, virtually everything else in the universe other than cats.
4. In the real world, therefore, depending on the context, that negative category is delimited to say dogs, such as when we are talking about a cat show as opposed to a dog show, or when we discuss the merits of keeping cats as opposed to dogs as pets. How we pick out “the other category” depends on the context, contextualism, in tum, means that the oppositional pair created is not a dualism but a dyadism.
5. Dualism implies permanence, as it is context-independent — hence, men are (in all contexts) superior to Women, mind/soul is superior to body (or body to mind in Biomedicine), humans are superior to non-humans, and so on. Under dyadism, as it is context-dependent, men are superior to women in certain contexts such as, in general, possessing greater physical strength, while women, in general, are superior to men, for example, in grasping nuances in emotional relationships; women can bear children but men cannot, and in this sense, men may be said to be “inferior” to women. Inherent inferiority or inherent superiority is not part and parcel of dyadic but only of dualistic thinking.
6. In dyadic thinking, the two terms in opposition in any one pair—“men”/” women” or “mind”/“body” —simply refer to different clusters of characteristics or functions in any one given context. The difference(s) focused on would not necessarily be carried over to other contexts. For example, a cat can catch mice, a dog cannot; so in the context of exterminating vermin, cats are opposed to dogs and are superior to dogs in this respect. But in the context of animals as pets, dogs and cats are both pets and so are different from and, therefore, opposed to cattle or chickens which are kept and then slaughtered for the market.
7. All oppositional terms, according to dyadism, involve contextualism, and can also be said to involve perspectivism, in the case of particular terms such as “big” /” small,” “above/below,” “tall” /* short.” When judged from a great distance, an object appears small, but nearer, it appears to be much larger. Relative to y; a is tall or above, but relative to z a is short or below. Relative to a chicken, a human is large but relative to an elephant, a human is small. What is above or below, big or small depends on the position of the viewer and the kind of viewer it is, on the distance between the viewer and the viewed, on the value standpoint of the viewer. Other pairings are sweet/bitter or hot/cold: if the person first eats a very sweet piece of milk chocolate, then a piece of dark chocolate, then the latter would taste even more bitter than if it were taken on its own without first having eaten the former and vice versa; if you first plunge your hand in cold water followed by plunging it into hot water, the hot water would feel less hot than it would otherwise be. Take weeping/laughing: we associate Weeping with something sad or tragic and laughing with something happy or funny —yet sometimes the most tragic of circumstances would it not weeping but laughing, and the laughing is to be understood as weeping but in another mode. This simply confirms the claim that perspectivism is context- dependent; hence, the significance of Contextual Thinking as the over-arching framework in the Chinese Mode of Thinking.
The examples earlier cited from the Zhuangzi are instances of perspectivism at work; the Laozi is also full of similar pairings such as big and small, up and down, inside and outside, beginning and ending, level and sloping, light and dark, sweet and bitter, advancing and retreating, gain and loss, weeping and laughing, and many others. [….]
8. Perspectivism emphazises that there is a conceptual link between the contrasting terms in the pair— that the concept inside (x) implies that of outside (y), far implies that of near, tall implies that of short, beautiful that of ugly. The concept x could only be properly grasped/understood by relating it to its conceptual contrast y as well as the situation and attitude of the individual in deploying the contrasting terms in the pair.
9. It means one cannot depart form context. Hence, the Contextual-dyadic Mode of Thinking is basic and fundamental. In particular, the Yinyang pairing which does not involve perspectivism but is pervasive in Chinese philosophy, science, and culture, through the ages, has come to be taken as paradigmatic of this kind of thinking. However, it could be that more humble pairings such as above/below, tall/short, or large/small involving perspectivism could have laid the foundation for its appearance; at least they all fall under the same (implicit) logical heading. Smith, 2008:24 observes: “(t)hese contrasts suggest a major source of inspiration for, if not the actual origins of the pervasive notions of yin and yang.”
10. The Yinyang pairing serves to bring out, more strongly than some of the other pairings, that the relationship between yin and yang goes beyond a mere conceptual relationship; chapters 6 and 7 have demonstrated the complicated relationships between them, namely, that empirically, causally, and ontologically, they are inextricably entwined with each other, acting as a harmonious Whole. The pairing and the harmonious Whole are empirically based because processes in Nature exhibit them— day is followed by night, night by day, Winter by Summer, Summer by Winter, heat by cold, cold by heat, life by death, death by life. Yuzou (universe) and Wanwu (especially organisms) repeat this cycle in an enduring manner. The pairing is ontologically grounded because the fundamental category in Yuzhou is Qi and Qi exists and operates in two modes, Qi-in-dissipating and Qi-in-concentrating modes— together they form a harmonious Whole as Em-ism, neither only energy nor ouly matter (to use modern language).
The pairing, under Wuxing, functions causally in terms of the Mutually Engendering and Mutually Constraining Modes (in the language of science today, the pair could be said to demonstrate feedback mechanisms at work). Yinyang does not refer to concrete things set in stone but on relationships in any given context—in the zhouye (daily) sequence, relative to night, day is yang and night is yin, but relative to day itself, the first half is yang-in-yang…, and the latter part of the day when sun gets weaker, it is yin-in-yang…. Relative to night itself, the first half is yin-in-yin…, and the second half is yang-in-yin…. (See *Liu, 1980: 48.)
In Nejjing/Suwen, Chapter 4. .., As rendered by this author: “In yin there is yin, in yang there is yang. From sunrise to noon, the yang of the sky is yang-in-yang, from noon to sunset, the yang of the sky is yang-in-yang, from midnight to dawn (when the cocks crow), the yin of the sky is yin-in-yin, from dawn to sunrise, the yin of the sky is yang-in-yin.”
Another example comes from the Yao-gua Model of the Yijing. Here s a version of the sequence of the Xiantian gua (according to the Shao Yong) which reads Qian(1), Dui (2), Li (3), Zhen (4), Xun (5), Kan (6), Gen (7), and Kun (8) as shown below.
This arrangement shows the trigrams as polar contrasts: the Qian gua occupying South and the Kun gua occupying North; the Li gua East and the Kan gua West, the Zhen gua Northeast and the Xun gua Southwest; the Dui gua Southeast and the Gen gua Northwest.
The Houtian (After-Heaven) arrangement (see chapter 5) illustrates the relationship between the trigrams and Wuxing.
Here, the Li gua now occupies due South and its polar contrast the Kan gua due North; the Zhen gua due East and its contrast the Dui gua due West; the Gen gua occupies Northeast and its contrast the Kun gua Southwest; the Xun gua Southeast and its contrast the Qian gua Northwest.
The trigrams could be arranged differently depending on the context of their application; they could occupy different positions in terms of Timespace—for instance, a different gua than the Qian gua, the Li gua could be used to stand for East/Summer/Heat/Yang depending on context. This accords with the over-arching Contextual Mode of Thinking; its account of polar-contrast pairings is dyadic, not dualistic as according to the latter, the respective status of the superior/privileged/the dominating and that of the inferior/non-privileged/dominated half of the pairing remained hierarchically unchanged, set in stone. Under the Contextual-dyadic Mode, the pairings form a harmonious Whole and so could, therefore, be argued to be a distinctive form of thinking, indeed, unique to Chinese civilisation and its culture.
This excerpt isn’t one-quarter of the way through the chapter, yet is enough to give a flavour for the ideal of contextual-dyadic thinking. The next section (11) reinforces “the analysis above by looking at an image of the pro-creation myth in Chinese folklore”.
Lee, Keekok. 2017. The Philosophical Foundations of Classical Chinese Medicine: Philosophy, Methodology, Science. Lexington Books. https://rowman.com/ISBN/9781498538886/The-Philosophical-Foundations-of-Classical-Chinese-Medicine-Philosophy-Methodology-Science.