Here is a highly incomplete list of the currently blocked terms, from Ng's extensive collection:

JUNE 4

天安门: Tiananmen (simplified characters)

坦克: tank

liu四: phonetic for 6-4

六四: 6-4

学潮: campus upheaval

ⅥⅣ: Roman numerals for 6-4

IIXVIIIIX: Roman numbers for 1-9-8-9

Jun 4th

陆肆: sounds like “liu si,” homophone for June 4

天安門: Tiananmen (traditional characters)

五月三十五: May 35, aka June 4

瓶反鹿死: Redress June Fourth

six四: 6-4

six four

TAM: abbreviation for Tiananmen

王维林: Wang Weilin, alleged “tank man”

春夏之交: Between spring and summer

The blocked terms are a mix of Mandarin and English, and a mix of the Latin alphabet and Chinese characters—and, for that matter, a mix of traditional and simplified characters. They are the result of censors deconstructing Tiananmen not as history, but as data. They treat the events of that day as a matter of semiotics as much as memory—events that can be broken down to atomic elements of meaning and then transmitted in words and numbers and letters and characters. (And also, in a couple of cases, in Roman numerals.) There are, it turns out, a number of ways to achieve that transmission.

Recognizing the power of today's anniversary, though, the censors have also escalated their attempts to filter memory. (They will likely also de-escalate those efforts very soon: "If past history is any indicator," Ng notes, "the most sweeping of these search blocks will likely be rescinded once this sensitive period has passed without incident.") Ng counted nine new terms that the PRC has blocked on Weibo for the 2014 anniversary. They include:

八九: 89

维多利亚公园: Victoria Park (site of vigil in Hong Kong)

VIIIIXVI: Roman numerals for 8-9-6

VIIV: 6-4

缅怀: nostalgia—a possible reference to Tiananmen Mothers

侏儒之歌: A song used in Tiananmen commemorations

You have to give the censors credit for cleverness, at least, as they engage in this coded game of cat-and-mouse. One other term that's been newly blocked? 2的6次方. It's a mathematical expression that, translated, means "2 to the power of 6." Which is 64. Or, yes, 6-4.

Via the Wall Street Journal

We want to hear what you think about this article. Submit a letter to the editor or write to letters@theatlantic.com.