旧金山的夏天里冷的一天比冬天里不冷的一天要冷。这个夏天的冬日在地球上其它地方很少见,要不是在旧金山住了十多年了。我不会有这个感性认识,即使有感性认识,也不一定能上升到理性认识。今天就是这样一个阴冷的夏日。刚迈出家门,就被一阵冷飕飕的风激了一下,我意识到身上没带房门的钥匙,想回去拿,又不禁觉得自己可笑,反正也不回来了,干嘛多此一举?迎面走来的是旧金山的条条街道和街道两旁的店铺。我熟悉这里的一切,一座座立正看齐的水泥大厦,川流的人群,还有来来往往的车辆。在水一般的车流里有私家车、出租车、卡车、货车,不时还有警车、救护车呼啸而过。一次我独自开车由犹他州进入亚利桑那州,一条笔直狭长的公路从我眼前一直延伸到天边。放眼望去,路的两边是沙漠,远处是山野, The cold day in San Francisco summer is colder than the cold day in winter. This summer’s winter is rare on the rest of the planet, or for more than a decade in San Francisco. I do not have this perceptual knowledge, even if there is perceptual knowledge, it may not necessarily rise to rational understanding. Today is such a cold summer day. Just got out of the house, was a chill wind irritation, I realized that the body did not bring the keys to the house, want to go back and get, can not help but feel ridiculous, anyway, do not come back, why not? San Francisco is the streets and streets of shops. I am familiar with everything here, a towering cement building, stream of people, as well as coming and going vehicles. There are private cars, taxis, trucks, vans in the watery traffic and police cars from time to time. Ambulances roar past. Once I drove alone from Utah to Arizona, a straight, long, straight road stretched from my eyes to the horizon. Looking ahead, the road on both sides of the desert, distant mountains,