舊地重遊

讀卡爾維諾的《看不見的城市》，感慨於他對城市精緻深入地描繪，也觸動我最近在幾個城市舊地重遊的思考。參觀這些城市的間隔都在十年左右：舊金山，聖迭戈，慕尼黑，維羅納，威尼斯。

如果不參考以前的照片，十年前的這些城市在我的記憶裡多是灰色的輪廓，即使我記得一些色彩，那也是罩了一層紗，像夢遊一樣。但是我會記著些許鮮明的細節，如果在實地得到驗證，表明我的確曾經來過這裡。第一次在這些城市停留的時間從一天到三年不等，然而如果不加入人的因素，十年後這些城市在我的記憶裡都佔有相同的空間，除非我在城市的街道裡一遍遍尋找可能的記憶。在遊歷過兩百多個城市之後，站在任何一個城市的任何 一條街道，你都會有一種似曾相識的感覺，但是如果你仔細觀察，總能找到一個城市區別於其它的特點。我之所以這麼糾結於記憶，並不是要生活在過去，而是每一次回憶都會有不同的人生體驗，舊的記憶不斷被新的經驗所修飾改變，歷史只在發生的那一刻是真實的。

舊金山

十年前，我陪著老母親遊覽舊金山，在這裡停留兩天。記憶裡只有金門大橋，漁人碼頭，姚明蠟像，市政廳，亞洲藝術博物館，中國城，吃煮螃蟹，穿越金門公園，以及在紅色的金門大橋下的遊船上，母親的滿頭銀髮被海風吹到腦後，她興高采烈地指著一群白色的海鷗笑。至於我們住在哪家旅館，吃的什麼早飯，穿的什麼衣服，在哪家飯店吃的螃蟹，金門公園裡有什麼花在開，我已經不記得了。如今再到漁人碼頭，就像從來沒來過一樣，除了碼頭的那群海獅似曾相識。舊金山這些地方沒有太大變化，只是它們的細節在我的記憶裡消失了。這也為未來的記憶留下空間，或許我會說，舊金山是金子做的城市，所有的雕像和房頂都是金子的，後來大地震把城市毀了，金子也成了記憶。現在重建的城裡只生活著老年人，年青人都搬到附近的新金山了，因為他們付不起房租，房價是被新移民抬高的。金門大橋本來是金子做的，大地震後重建變成現在的樣子。中國城本來是兩百年前修鐵路的中國勞工聚居地，現在已經被墨西哥人佔領了，他們是這裡的新富。雖然招牌還是中國字，店裡已經看不到中國人了。如今巨人體育場旁邊的碼頭是以盛產精靈寶魚而留下記憶的，連帶著體育場裡巨大的可口可樂瓶，十年後也許這個遊戲已經不存在了，但是這個記憶難以磨滅。

聖迭戈

聖迭戈是我遊歷美洲的第一個城市，因為參加學術會議在那停留四天。藍天大海，航空母艦，日本壽司，以及巨大的會議中心和幾萬科學家都令我興奮。那年見過的同事朋友也都印象深刻，包括北大醫學院和夏威夷大學的兩個教授。然而細節呢？站在自己的牆報前，我還記得牆報的黑色背景和題目；一個年輕的華人學生向我提問，他小個子，很清秀；一個剛獨立的華人女副教授在招聘助手，她穿深色西裝，很嚴肅；一個美國華人科學家談起我們都認識的一位瑞典科學家，他個子高大，圓臉微胖很和善；另一個抱著小孩的美國華人科學家笑著說我沒有做功能實驗。也許我還去了動物園，看到很多鹿。最近再遊聖迭戈，能夠印證的只有航空母艦，我不能確信那是曾經參觀過的航空母艦，除了它還在原來的位置，我不記得一點細節。我也不知道十年前看到的動物現在是否還在那裏，即使在，我也認不出來。上次看了很多鹿，這次看了很多考拉。現在的動物都有了名字，可惜我沒有記它們的名字，所以下次來我還是不知道上次看到的是哪一隻。這次停留兩天，我發現找一家合意的咖啡店吃早餐很不容易，晚上吃的中餐十分差勁，立交橋下成群的流浪漢散發著騷臭，整個城市都是毫無特色的建築，所有新印象整體顛覆了我記憶裡明朗的聖迭戈形象；也許這正是一個城市的真實的兩面，你記住什麼完全取決於你當時的心情。晚上在酒吧邊喝酒邊吸著胡卡水煙，開始感慨十年的變遷，於是短信給當初在這一起玩的朋友，他已經不確信是否曾經跟我在這一起玩過了。

慕尼黑

慕尼黑是我在歐洲呆過時間最長的一個城市，也是記憶最深而變化最小的一個城市。在中央火車站還能找到那家時常光顧的郵票店；在奧運村還能沿著以前散步的小路走到附近的研究所；在研究所還能看到那扇時常在晚上唯一亮著燈的窗子。Scheidplatz地鐵站橘色的站牌和記憶裡一樣顯眼，百年研究所白色的樓房和夢裡一樣沈靜，樓前的黑楊看不出粗壯了多少，小花園裡的鞦韆還在那裡悠蕩。當年購買食品的亞洲店還在賣同一個牌子的方便麵，站在有軌電車駛過的街道上你會感到時間的停滯，如果不是自己已經變老。當然也有一些變化—中央車站附近新開了很多店鋪，從文字看有中國的，印度的，土耳其的，阿富汗的，北非的，中東的；城裡又多了一個博物館，正在展覽反叛一代的藝術；烤豬腿還在，但沒有第一次吃時的味道了。馬可說，一個沒有變化的城市最容易被記住，但是城市本身會因沒有變化而衰落消失。慕尼黑好像是個例外，也許他內在的變化我們在外表是看不見的。我們記住某個場景往往是因為有人的互動，三年的生活會積累大量的記憶，碎片連起來就是故事。看到體育館我會想起和誰一起滑冰，游泳，打乒乓球；看到電影院劇院我會想起和誰一起看的什麼電影歌劇；看到博物館我會想起和誰一起欣賞古典繪畫，現代藝術，或是科技進步；看到酒吧飯店我會想起和誰一起喝酒吃飯聊天；也有自己一個人經常散步的地方，逛商場的地方。儘管這裡不是我生活過最久的城市，卻是我生活最豐富的城市，因為在那個年齡，那個地方，遇到了那麼一群人。

維羅納

我去過義大利的大部分城市，最喜歡的卻是維羅納，也許她是我遊覽的第一個義大利城市，也許是那一刻她正合我的心境，從此便刻在記憶裡。那一年的復活節，我住在山上的一個教堂裡，禮拜堂裡大概擺放了一百多張雙層床，住著往來的世界各地的青年行者。教堂在山頂上，山的對面有一個巨大的十字架，十字架的周邊裝著成串的霓虹燈，黃色的燈光在夜裡格外明亮。早晨吃過簡單的麥片粥，我就下山來到城裡。太陽還沒有出山，整個城市籠罩在霧中，我沿著阿迪傑河，穿過靜靜的小巷。街上空無一人，和夢境裡一般：石路，古橋，蜿蜒河水滔滔；白牆，紅瓦，瀰漫霧氣昭昭；鐘聲悠遠，鳥鳴環繞。圓形劇場和朱麗葉舊居本是這裡的名勝，我的印象卻不深。十年後舊地重遊，再沒有當初的感覺。

威尼斯

威尼斯是水上的城市，馬可波羅的故鄉。在《看不見的城市》裡，卡爾維諾借馬可之口描述了她遙遠又親切，若有若無的印象，不忍輕易回憶。這正是坐在船上看遠處風景的感覺，起起伏伏，時隱時現。我十年前在這裡的記憶也是如此。水上巴士從羅馬碼頭到利多碼頭要沿著運河和海灣走半個小時。夜裡的水一片漆黑，兩岸林立的樓房裡飄出隱約的燈火，黃色的路燈在黑暗裡流動，只有發動機的聲音和水流過的聲音劃破寂靜的夜。早晨的威尼斯籠罩在霧氣裡，在開往穆拉諾和布拉諾的船上，遠處傾斜的鐘塔若隱若現，這神秘朦朧感在電影《威尼斯疑魂》有完美的紀錄；站在船頭，吹著腥咸的海風，看古老的建築在霧靄裡飄移，有種無名的傷感。聖馬可廣場，狂歡節的面具，小巷裡的貢多拉，穆拉諾的五彩玻璃，布拉諾的蕾絲織品，和船上的記憶比要淡得多了。最近重遊水城，還是如此。

Swimming

California's weather is wonderful, sunny everyday. In the summer, It's not hot with cozy breeze. I usually go swimming in the nearby pool around four or five o'clock in the afternoon. Sunshine breaks through the water to the bottom, leaving a chain of light and shadow. The celeste pool water mirrors the tree outline. Occasionally, a few stray ducks fly in, reluctant to leave. This week in Rio de Janeiro came the anecdote that the water in Olympic Games diving pool turned from blue to green overnight, whereas the swimming pool next to it kept blue. It was first blamed to the algae propagation due to the hot weather and little ventilation; the next day, the blue swimming pool turned green too, it was then blamed to a big change in pH of the water due to too much people using the pool and short of chemical indicators. Anyway, either hypotheses may be correct and there may be other causes too. I am afraid there is no time for A/B testing—the organizers said there was no health risk and the athletes play as usual.

Jumping into the water, stretching, adjusting the breath, and controlling the tempo, I began to practice holding breath. In the the bottom of the pool, the lane marking line is made of dark brown mosaics. Each mosaic is about 2x2 square inches and nine small squares makes a big square. The big squares are connected one by one from one end to the other end of the pool, about 25 feet long. I held a breath and dived into the the water, starting from one end to the other end and counting the numbers of small squares. I tried several times, could only count to one hundred to the most, when I insisted for one minute. Compared with playing Rubik's cube underwater, my game of counting numbers is much easier. According to the theory of evolution, human ancestors are fishes living in the sea. Having gills, they can dive deep into the sea. I wonder if they have their own language and decimal number system. If human invented decimal number system because there are ten fingers can be used for counting, the fish probably will never have their own number system because they can not see their bodies. Of course, those long fishes are excepted. However, long fish like eels have smooth bodies and nothing can be counted, unless they count how many circles they can rotate around themselves, but this is not a fixed variable. Thus the sea give the fishes freedom to swim but deprive of their freedom to think.

Roaming in the water over time, I began to feel myself turn into a fish,  intermittently breathing on the surface. Even a lonely fish can feel pleasant in the water. This pleasure is probably due to the feeling of buoyancy the water making of the body. The gravity is partially offset by the buoyancy, giving a feeling of unusual lightness. Humans have been in the pursuit of this feeling of escape from the shackles of gravity—swimming, racing, gliding, aircraft, spacecraft. The ancient people dream to get into the Heaven, the modern people dream to go to Mars (the gravity on Mars is 1/3 of that on Earth).

Fish is often the projecting target of human emotions. It can be done on the shore, without getting into the water. Two thousand years ago, standing on the bridge at Ho Leung, Chuang Tzu projected his happiness onto the river minnow: "Minnows swims freely and they are happy" (<Chuang Tzu.Autumn floods>). Of course, the minnows are maybe happy, maybe not happy, maybe they do not know if they are happy or unhappy. But never mind, Chuang Tzu felt very happy himself, so he thought the minnows were happy like him as well and that was enough. Of course, if you get into the water, there will be more happiness. Humans tend to share their happiness with others. I have had the experience of deep-sea diving and swimming with the fish schools together, and what did I feel? Probably quadratic that of Chuang Tzu.

Another famous exchange between human and fish occurred two hundred years ago in Germany. Christian Schubart, a famous poet and composer,  was imprisoned, when he wrote a poem for a trout fishing scene— "In a clear stream in happy haste, the imparted trout darted by like an arrow" (Scott Horton translation <Die Forelle >), the poet also felt the quiet sweetness; but as the fisherman made the stream opaque to catch the trout, the poet expressed great anger, compassionating their lost freedom. Schubart projected his own feeling onto the the trout, which is naive joy of young people. If you are Schubart, you'd rather be free than in prison; if you are trout, you prefer clear stream to opaque stream and fisherman's fishing hook. Later this poem was composed into song and chamber music by Franz Schubert and the famous <Trout Quintet> came into being; but it only expresses the happiness there.

It's Italian poet Euogenio Montale who made this projection to its extreme. He is a poet after World War II during the reconstruction period. In <eel>, he depicted in detail the life cycle of eel in which he demonstrated his strong will in pursuit of life. Like people who leave hometown in their young and return in their old ages, eels born in the Baltic sea will roam a long way in very young ages to the freshwater in the south, where they grow up two or three decades later before returning home to spawn and then die. Human leave their hometown in pursuit of a better life; eels probably do for the same purpose. After all, the resource-rich south is warmer and may has less predators, the hardship of long distance could be paid off. Eel do not eat on their way back home but just accumulate energy for spawning once they are in the home sea. Obvious the life in the south is easier than that in the north for eels. But Montale thought the opposite—eels abandon their resourceful life in the north and take a long trip to the harsh environment in the south to survive ("the green spirit who seeks/life there only/ where drought and desolation gnaw" Millicent Bell translation <eel>), which seems against common sense. 

游泳

加州的天氣真是太好了，每天都是晴空萬里。夏天裡，微風拂面，又不是很熱。我通常下午四五點鐘去小區的游泳池裡游個一小時。陽光射入池底，留下環環相扣的光影，湛藍的水面映著樹的黑色輪廓，偶爾有幾隻迷路的鴨子飛進來，樂不思蜀。這週里約熱內盧傳來奇聞，奧運賽的跳水池一夜間由藍變綠了，而它比鄰的游泳池卻還保持藍色。開始說是天氣熱通風少海藻繁殖造成的；第二天藍色的游泳池也變綠了，又說是人多酸鹼度改變大，化學指示劑加的不夠。不管怎樣，兩種假設都有可能成立，還可能有其它原因，恐怕沒有時間做A／B測試了，主辦方說沒有健康危險，運動員也如常發揮。

跳進水裡，伸展四肢，調整呼吸，控制節奏。我開始練習憋氣，池底的泳道標誌線是由深棕色的馬賽克拼成的，最小的單位大概是2x2英吋的方塊，9個小方塊組成一個大方塊，大方塊一個接一個連起來從一端到另一端，大概25英呎。我憋足一口氣潛到水裡，開始從一端向另一端數小方塊。試了幾次，最多數到一百，也就堅持一分鐘時間。比起在水下玩魔方，我這個遊戲要容易得多了。按照進化論，人類的祖先是魚，生活在海裡，有腮，能潛到很深的海底，不知道他們有沒有自己的語言和文字以及十進位數字。如果人發明十進位數字是因為有十個手指可以用，那魚大概永遠不會有自己的數字系統，因為他們看不見自己的身體；當然那些超長的除外，但即使超長的像鰻魚渾身光滑又沒什麼可以計數，除非他們計數自己繞自己幾圈，可是這又是個不固定的變量。所以大海給了魚游泳的自由卻剝奪了他們思考的自由。

在水裡漫遊，久而久之，感覺自己變成了魚，除了有間歇地出來透一口氣。即使是一條孤獨的魚，在水裡也有種愉快的感覺。這種愉悅大概來源於水給身體的浮力。這浮力抵消了一部分重力，給人一種不同於平常的輕的感覺。人類一直在追求這種逃離重力束縛的感覺—游泳，賽車，滑翔，飛機，航天飛機。古代人的理想是上天堂，現代人的理想是去火星（火星的重力是地球的1/3）。

魚常常是人類情感的投射。不用下水，站在岸上就可以了。兩千多年前莊子站在濠梁的橋上把自己的心情投射到河裡的鰷魚上：“鰷魚出遊從容，是魚樂也” （《莊子.秋水》）。 當然鰷魚也許快樂，也許不快樂，也許不知道自己快樂不快樂。不過沒關係，莊子感覺到自己很快樂，推想鰷魚也一定跟他一樣快樂，這就足夠了。當然下了水會有更多的快樂，人類總有分享自己快樂的意願。我曾經體會過在深海潛水跟魚群同遊的感覺，大概是莊子的二次方。

另一次有名的人魚交流發生在兩百多年前的德國。詩人兼作曲家舒巴特身陷囹圄，聯想到以前在河邊看到的漁人釣鱒魚的情景—“在一條快樂急流的清澈小溪，一群鱒魚像箭一樣四處飛躍”（《鱒魚》）， 詩人同樣感到了甜美的愉悅心情；但是在漁人弄混了溪水釣到上勾的鱒魚後，詩人又表達了極大的憤怒，為它們失去了自由而惋惜。舒巴特投射到鱒魚身上的是幼稚快樂容易上當的年青人，也是他自己的經歷。如果你是舒巴特，你寧願自由而不是監獄；如果妳是鱒魚，妳寧願在清澈的小溪亂蹦也不願上漁人的釣勾。後來這首詩被弗朗茨.舒伯特譜了曲，就是著名的《鱒魚五重奏》；不過這裡只有輕鬆愉悅的表達了。

把這種人魚投射做到極端的是義大利詩人埃烏傑尼奧.蒙塔萊。他是二戰後歐洲重建時期的詩人；在《鰻魚》裡，在細膩描繪鰻魚生命週期的同時，他在鰻魚身上投射了對生命意志的強烈追求。就像少小離家老大歸的人一樣，鰻魚出生在北方的海裡，小時候背井離鄉漫遊到南方的河水里長大，二三十年後再回到故鄉產卵，然後死亡。人類遷徙是出於追求更好的生活，鰻魚大概也是出於同樣的目的，畢竟南方溫度高資源豐富敵人也許更少，即使路途遙遠艱辛。鰻魚迴游的路上是不吃東西的，只是靠在南方積攢的能量游到北方老家產卵，可見南方應該比北方生活好。但是蒙塔萊卻認為鰻魚是放棄北方的優越，到南方的艱苦環境中生存的（“綠色的意志尋找／生命只在那／乾旱與荒蕪”《鰻魚》），這似乎有點不合常識。

這些投射都是人在吃飽了之後做的事，在吃飽以前恐怕只有“人為刀俎，我為魚肉”的聯想了。考慮著是紅燒還是清蒸，我們跟冷酷的漁人就沒有什麼區別了。

My Bianchi vintage bike

I bought a bike—Italian blue Bianchi vintage. At first I thought she is turquoise, then I Googled and she is not turquoise. Bianchi website said she is celeste, Bianchi green, or sky blue, but she looks like turquoise a lot, may in fact is really a mixture of celeste and  turquoise. I really like turquoise, which reminds me of classic cars in Cuba, as well as the Greek sea—clear and bright, full of sunshine. Bianchi green is also called Italian green, or sky blue; it appears to be first used by Eduardo Bianchi on his Bianchi bike. Legend had it that Bianchi founder Eduardo Bianchi designed a bike for a queen with the color of her eyes, which is this Bianchi green. It was also said that it is the color of Milan's sky at noon.

This is a road bike, which is to be rode on paved roads. She's got thin wheels, curved handles, and 11x2 shift, but she is not used for racing now because her frame is made of chrome steel, whereas that of popular racing bike now is made of carbon, which is of course much lighter than chrome steel, so my bike is slower than the racing bike. How much slower?  About five miles per hour. That is, if an amateur player rides 120 miles, it will take him 6 hours by the racing bike but 8 hours by my vintage bike. Why do I want to buy an outdated vintage bike? Like the ad says, Bianchi vintage series is for those who live in the present but love the past. Maybe I was this type of person. To remedy the weakness of brittle carbon material, double reinforcement is used in racing bike, which makes him look cumbersome, despite the fact that he is much lighter. Anyway, from the aesthetic view, I prefer slim vintage design; moreover, I have no interest to ride for competitions, but only want to plan trips around the world, so this is the ideal choice.

Although I have yet to carry out my global riding plan,  my Bianchi has gone around half the Earth. Steels and parts were transported through he Taiwan strait from mainland China to the Taiwan island. This bike is assembled here, together with the Japanese Shimano shift. Finished bikes are put into the containers, which are transported through the Taiwan Strait, South China Sea, Straits of Malacca, Indian Ocean, Arabian Sea, Red Sea, Suez Canal, Mediterranean, and arrive at the port of Naples, Italy. They are then loaded into a truck and shipped to the Bianchi factory in Treviglio near Milan. My Bianchi is then transported to Bianchi retailer shop in Modena.  At the moment I completed the transaction with the retailer by shaking his hands, I see all the people appeared by this amazing bike— the inventor of wheels, Karl Drais the inventor of bicycles, a former orphan Eduardo Bianchi, the green-eyed queen, the modern designer in front of the computer, the racer on the road, the steel worker next to the furnace, the lathe worker by forging machines, the rubber field worker, the assembly worker in the factory of bicycles, the maintenance worker in bike shops, and even the boy in the film "bicycle thieves" who can remember the serial number of his father's Bianchi bike.

The trip is not over yet. I took my Bianchi and boarded the plane, through Bologna and Frankfurt, flying over Siberia, Canada, and finally arrived at San Francisco, California. This is what happened to Bianchi NV0004334L in year zero. What happened next for her adventure? We do not know yet.

我的比安奇老爺車

我買了一輛自行車，義大利產的，蔚藍色比安奇。起初我以為是綠松色，後來谷歌了一下，原來不是綠松色。比安奇網站上說是湛藍色或比安奇綠，但是她看上去很像是綠松色，實際上可能真是混合了綠松色。我非常喜歡綠松色，她讓我想起古巴的老爺車，還有希臘的海，也是這種顏色，清澈明朗，滿是陽光。比安奇綠也叫義大利天藍色，看來是比安奇最早用在他自行車上的。傳說比安奇的創始人愛德華多.比安奇為一位王后設計車的時候用了她眼睛的顏色，就是這種比安奇綠。也有人說那是中午十二點時米蘭天空的顏色。

這是一輛公路車，也就是在鋪了瀝青的公路上騎行的，她有纖細的輪子和彎曲的把手以及11x2的變速，但她不是當前的比賽用車，因為她的骨架是鉻鋼的，而現在流行的賽車是碳的。碳當然比鋼輕很多，所以我的車比賽車要慢很多。慢多少呢？我後來比較了一下，大概五英哩每小時。也就是一個業餘選手要騎行120英哩，用賽車需要6小時，用我的車需要8小時。我為什麼要買一輛過時的老爺車呢？就像比安奇收藏系列的廣告所說，這種車是為那些生活在現在但是留戀過去的人準備的。也許我就是這類人。因為現代賽車為了補救碳材料脆性大的弱點而使用了雙層加固，所以他的骨架粗大，顯得很笨重，儘管實際上他要輕很多。不管怎樣，從審美上考慮，我更喜歡苗條的老爺車設計；更何況，我沒有參與比賽的慾望，只有環球旅行的計劃，这是最理想的選擇了。

雖然我還沒有實施我的環球計劃，但是我的比安奇已經繞了大半個地球了。鋼材和零部件通過臺灣海峽被從中國大陸運到臺灣島。在這裡自行車被組裝完成，再加上日本禧瑪諾的變速器。成品車被裝進集裝箱，通過臺灣海峽，南中國海，馬六甲海峽，印度洋，阿拉伯海，紅海，蘇伊士運河，地中海，到達義大利那不勒斯港，再被裝進卡車經過公路被運到米蘭附近的特萊維奧，比安奇工廠所在地。我的比安奇車接著被運到摩德納的比安奇零售店。當我完成與零售商交易跟他握手的一瞬間，我看到這神奇的車上浮載的所有的人—發明輪子的原始人，發明自行車的人卡爾.德萊斯，曾經的孤兒愛德華多.比安奇，綠眼睛的女王，電腦前的現代設計師，公路上的賽車手，高爐旁的煉鋼工人，車床前的鍛造工人，橡膠場的壓胎工人，自行車場的組裝工人，自行車店的調試維修工人，甚至電影《自行車賊》裡的記住比安奇車編號的小男孩。

旅行還沒有結束。我帶著我的比安奇登上飛機，經過博洛尼亞，法蘭克福，飛越西伯利亞，加拿大，最後到達加利福尼亞的舊金山。這是比安奇NV0004334L元年發生的事。後來發生了什麼，她又有什麼奇遇？我們還不知道。