Dynamic zero

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We've been hearing about "zero Covid" since early in the year 2020.  Even though such an approach never seemed feasible to me, it was always fairly clear what the Chinese authorities meant by it:  through "public health measures such as contact tracing, mass testing, border quarantine, lockdowns, and mitigation software in order to stop community transmission of COVID-19 as soon as it is detected." (source)  In other words, "Find, Test, Trace, Isolate, and Support" (FTTIS).

The Chinese term for such a policy is "qīng líng zhèngcè 清零政策", where "qīng 清" means "clear; clean; thoroughly; completely", "líng 零" means "zero", and "zhèngcè 政策" means "policy".  Fair enough, though, as I indicated above, I never thought that, in dealing with a communicable virus, it was a practicable approach.  Apparently, in due course, the PRC authorities — though they strove, through the most stringent application of FTTIS measures — came to the same conclusion.  Eventually, they started to refer to their modified "qīng líng 清零" ("zero [COVID]") policy as one of "dynamic zero", the Chinese for which is "dòngtài qīng líng 動態清零", where "dòngtài 動態" signifies "dynamic".  Here they lost me, because, for the life of me, I simply could not comprehend how "zero" could be "dynamic".

The absolute value of 0 is 0.  Once the Chinese authorities started to talk about "dynamic zero", it seems to me that they admitted defeat for their "zero" policy.  Trying my best to comprehend what they meant by "dynamic zero", I looked into instances in mechanics and mathematics where "zero" and "motion" come together.

There's "zero moment point" in robotics:

Zero moment point is a concept related with dynamics and control of legged locomotion, e.g., for humanoid or quadrupedal robots. It specifies the point with respect to which dynamic reaction force at the contact of the foot with the ground does not produce any moment in the horizontal direction, i.e., the point where the sum of horizontal inertia and gravity forces is zero. The concept assumes the contact area is planar and has sufficiently high friction to keep the feet from sliding.


I couldn't make that work with regard to public health policy for dealing with a virus.

How about "zero-sum game" in mathematics?

Zero-sum game is a mathematical representation in game theory and economic theory of a situation which involves two sides, where the result is an advantage for one side and an equivalent loss for the other. In other words, player one's gain is equivalent to player two's loss, therefore the net improvement in benefit of the game is zero.


Since Chinese officials are fond of talking about win-win situations, I don't think this is what they had in mind with "dynamic zero" for treating the scourge of SARS-CoV-2.

All right, then, I'll go directly for "zero dynamics".

In mathematics, zero dynamics is known as the concept of evaluating the effect of zero on systems.  The idea was introduced thirty years ago as the nonlinear approach to the concept of transmission of zeros. The original purpose of introducing the concept was to develop an asymptotic stabilization with a set of guaranteed regions of attraction (semi-global stabilizability), to make the overall system stable.


No go.  The PRC authorities could not have been thinking of that when they coined the expression "dòngtài qīng líng 動態清零" for coping with the coronavirus pandemic that erupted in the city of Wuhan in late 2019.

As I did when I first encountered "dòngtài qīng líng 動態清零", I cannot help but think of "dynamic zero" as a kind of grand waffling that, in effect, bamboozles whomever is the object of such rhetoric.  Unfortunately, the CCP is stuck with "qīng líng 清零" ("zero") since that's what they hitched their SARS-CoV-2 wagon to more than two years ago.  Now that it has been proven unachievable, the best they can do is retrofit their zero wagon with a "moving diathesis" (the literal meaning of the two morphemes that constitute "dòngtài 動態" ["dynamic"]).

Before posting, I will add two items that I received from China just moments ago, one the latest pronouncement on "dynamic zero" from official PRC media, the other from a Beijing citizen who is right now living through "dynamic zero" procedures and operations.


Li Yang, "Dynamic clearing is both scientific and effective", China Daily (6/18/22).

It is noteworthy that here the authorities have abandoned the English word "zero" as the once preferred translation for "qīng líng 清零" and have substituted "clearing".  They may have done so because they finally realize how absurd "dynamic zero" sounds to Western ears.  The problem is that the relevant Chinese term is still "qīng líng 清零", which conveys the idea of "clear zero".  No way around that in Chinese, and "dòngtài 動態" is still "dynamic", whatever that is supposed to imply in conjunction with "clearing" or "zero".

Before moving on to the Beijing citizen's observations about how "dòngtài qīng líng 動態清零" ("dynamic clearing / zero") is being worked out on the ground in the PRC at the present time, I will just add a contextual note about the concept of "qīng 清" ("clear") from another field with which I have been intimately involved for decades in China, namely, archeology.  Although superficially seemingly straightforward, one of the hardest terms for me to translate from excavation reports was "qīnglǐ 清理" (lit., "clear-order").  I knew full well that overall it was a verb meaning something like "sort out; check up; put in order", but never felt comfortable comprehending the nuances of the constituent morphemes.  I feel the same sense of unease about "qīng líng 清零" ("clear zero").  Bear in mind that, before it was rushed into use for the current "zero [Covid control]" policy, "qīng líng 清零" started out in literary texts as an adjective implying "lonely; lonesome; solitary; desolate".  More recently, it was employed in computing as a verb denoting "to reset; to clear the memory".  From there, it was adapted by Chinese epidemiologists in the sense of "to reduce to zero; to zero out".  That may be their goal, but it is not happening, despite their fiercest efforts at FTTIS.


From an upstanding Beijing citizen:

Apart from "dynamic zero" (dòngtài qīng líng 动态清零“), we hear more like "shèhuì miàn qīng líng 社会面清零“ ("social zero")、”shèhuì miàn dòngtài qīng líng 社会面动态清零“ ("social dynamic zero"), etc. I don't care to understand what the government means by these terms, neither do I think others would care. All I can see is that people in Beijing take PCR tests everyday since early May and those who live upstairs or downstairs or adjacent to a positive case are removed from their home to quarantine. And the video clips and articles about the suffering and ridicule are zeroed. 

You see how the big whites (dàbái 大白)are sanitizing the streets in the video. Can't imagine anything more absurd! But I know there will be more, sadly.

Days ago when a Shanghai man was threatened by the police that if he didn't comply with the quarantine regulation, his succeeding three generations would be impacted, he answered: "This is our last generation. Thank you."

The fluidity of dynamic zero is far from achieving stasis.


Selected readings

  • "Duang" (3/1/15) — "quantum dynamic view of the atom" (here)
  • "Blocked on Weibo" (8/23/13) — in a book published in 2013, "Dynamic China" was listed as being blocked in China


  1. KeithB said,

    May 19, 2022 @ 8:53 am

    My HP-71 computer/calculator has the concept of +0, 0 and -0. (Since it is the first handheld to implement IEEE 854-1987, it is probably part of the standard.)

  2. bks said,

    May 19, 2022 @ 8:55 am

    "Zero tolerance" laws in the USA have met similar fates.

  3. Terry K. said,

    May 19, 2022 @ 9:07 am

    I imagine "dynamic zero" as being a kind of rounded-to-zero sort of thing. Like the "zero sugar" juice beverage I bought recently that has a smidgen of actual fruit juice, and thus a tiny amount of sugar, but less than half a gram, low enough to show up as "zero" in the nutrition facts. (And there was a foot note by the ingredients indicated the juice adds a "negligible" amount of sugar.)

  4. Andy Stow said,

    May 19, 2022 @ 10:18 am

    Makes me think of the "Vision Zero" goal to eliminate traffic deaths. Even if you don't think it's realistic, does it make sense to have a goal of "just" 10,000 USA deaths. The goal should be zero.

  5. Theo said,

    May 19, 2022 @ 11:55 am

    >> As I did when I first encountered "dòngtài qīng líng 動態清零", I cannot help but think of "dynamic zero" as a kind of grand waffling that, in effect, bamboozles whomever is the object of such rhetoric.

    Is there a term to describe such constructions?

    For inspiration:
    – "All animals are equal, but some animals are more equal than others."
    – "Democracy with Chinese Characteristics"

  6. Viseguy said,

    May 19, 2022 @ 1:37 pm

    Sounds like classic doublespeak. Lose-lose for genuine communication.

  7. Mark Hansell said,

    May 19, 2022 @ 1:51 pm

    Zero still means zero, but what is "moving"? I guess it's the goalposts….

  8. Philip Taylor said,

    May 19, 2022 @ 1:51 pm

    Re. Terry's "zero-sugar juice beverage", I recently attended a meeting at which the majority of those present wanted to promote the idea of a "plastic-free <name of town>". I found it necessary to point out that all who had spoken in favour of the idea had placed a (plastic) mobile 'phone on the desk in front of them.

  9. Dan Faulkner said,

    May 19, 2022 @ 2:30 pm

    This reminds me of the Partial Zero-Emissions Vehicle (PZEV), which seems to have arisen from a similar clash between ideals and reality. https://en.wikipedia.org/wiki/Partial_zero-emissions_vehicle

  10. David Morris said,

    May 19, 2022 @ 3:33 pm

    The current road safety plan in New South Wales includes 'Towards Zero'. They can call any reduction in deaths a success.

    Mobile phone plans are often priced at 'zero dollar' (plus those other dollars).

  11. Chester Draws said,

    May 19, 2022 @ 11:29 pm

    I wonder if it means that there will be cases, but each time they will get it back to zero again. So that zero is repeatedly reached, even if it is breached from time to time.

    Sort of like the person who "always has an empty in-tray". That's literally not possible if any work comes in, but makes sense if the tray is usually brought back to empty pretty quickly.

    The exact opposite of "learning to live with it".

  12. Isoraqathedh said,

    May 20, 2022 @ 3:05 am

    I find that the adjective just means "it is like that but it tastes different", i.e. it is a completely meaningless modifier that serves to change the definition of the noun in an arbitrary way.

    This is not at all limited to China, as Europe and America are wont to use "strategic" in front of every single international relations policy to mean, from what I can tell, "it'll be that thing, if you give me enough time and money to demonstrate it" or "I'm using that thing as a means to other ends".

  13. Isham Cook said,

    May 20, 2022 @ 5:16 am

    Whatever the Chinese authorities mean by the term “dynamic zero”, I think it’s quite straightforward. Covid cases will never stay “zero” unless there is constant, active movement, dynamic measures, to keep it at bay. Hence the endless and increasingly invasive interventions and restrictions.

  14. Victor Mair said,

    May 20, 2022 @ 9:14 am

    From Nick Tursi:

    It seems on par with “jumbo shrimp” and “cold as hell”.

  15. Peter in Philadelphia said,

    May 20, 2022 @ 3:05 pm

    They don't know nothing.

  16. Peter Taylor said,

    May 20, 2022 @ 4:29 pm

    Another one to consider is zero-point energy, the idea that in a real-life physical system the minimum energy state has non-zero energy. That could maybe be stretched to the CoVID policy of "Zero cases is impossible, but we can cool the system as much as possible and minimise the case load".

  17. unekdoud said,

    May 21, 2022 @ 1:44 am

    Zero-point energy is dynamic in a literal sense – extract all the energy you can, and the vacuum still wiggles. But I don't think Heisenberg uncertainty is directly applicable to pandemics.

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