Andy is teaching an undergraduate algorithms class that combines three regular courses: the discrete math and probability course, the algorithms course, and the computability courses. (CS70, CS170 and CS172 in Berkeley-speak.) To make things more interesting, he teaches the course in English. When a foreign visitor is here, Andy always invites him or her to talk about something, anything, in the class for one 45-minutes period. (Classes are 45-minutes periods followed by 5 minutes of break.) Yesterday was my turn.

As usual, things are done in style. I meet Su Chang in her office, and she walks me downstairs, where Andy’s driver is ready to drive us to the building where the lecture is. There, Su Chang walks me up to the classroom. We get there just while a military march is playing to mark the end of a period. For people who are used to hang out with celebrities, this would be no big deal, but being with a person who has an entourage is really amazing to me. Andy is there and he has just finished teaching (the class is two periods).

When another march plays in the loudspeaker, Andy introduces me to the 100-plus students “This is professor Luca Trevisan, from the University of California at Berkeley.”

“Ooh” the whole class goes, when Andy says “Berkeley.” This is quite unexpected: people in America hardly know that there is a university in Berkeley. But then, I realize, these are third year computer science students in the top engineering school in China. Applying to graduate school in the US must be very much on their mind, so it’s no wonder that they have researched American schools and they have come across Berkeley. In any case, it is surprising that students who have Andy as a professor can be impressed by anything.

I have decided to give a lecture on zero knowledge, motivating it with a password protocol problem, and I talk about quadratic residuosity instead of graph isomorphism. The students appear to genuinely understand and enjoy the class, and the march rings the moment I finish the proof that there is a simulator.

Andy invites me for lunch, “We are going to Pizza Hut.” “Oh no!” I say, before I can catch myself. Andy is unfazed by my rudeness and asks me what I would like. “Something Chinese?” I suggest assuming we would go to one of the Chinese fast food places around campus. Instead, we go to the Fancy Place of Tuesday night, where Andy orders a veritable feast.

Hoeteck is meeting a high school friend from Singapore who is in Beijing for business, and I spend the afternoon visiting the Beijing University campus. People say that Tsinghua is the MIT of China, and Beijing University is the Harvard. Famous for its Humanities department, Beijing University has a beautiful campus with a lake in the center, elegant buildings, and better-dressed students.

The evening turns more adventurous than usual, and I end up doing many new things, such as dining at a Chinese fast food place, taking the subway, seeing a working-class Beijing apartment, and joining a gathering made mostly of middle-aged Western expats parading around their young Chinese dates (I pay \$5 for a Heineken; dinner for two was \$4). I am not judging, because as president Bush’s favorite philospher said, “Judge not etc. etc.” and I, for one, don’t like to be judged. But next time people tell me about post-colonialism and white privilege (we use such words a lot in San Francisco), I promise I won’t roll my eyes. Berkeley’s star power is put in its more proper place. “What do you do in America?” “I am a professor at Berkeley” “Bay-kay-lee?” “That’s right.” “Is it an egineering school?” (them fighting words!) “No” “And what are you doing here” “I am lecturing at Chin-hoo-uh” “Qinghua? WOW!”.