一个人命里不见得有太太或丈夫，但绝对不可能没有朋友。即使是荒岛上的鲁滨逊，也不免需要一个“礼拜五”。一个人不能选择父母，但是除了鲁滨逊之外，每个人都可以选择自己的朋友。照说选来的东西，应该符合自己的理想才对，但是事实又不尽然。你选别人，别人也选你。被选，是一种荣誉，但不一定是一件乐事。来按你门铃的人很多，岂能人人都令你“喜出望外”呢？大致说来，按铃的人可以分为下列四型：
A person may have no wife or husband in their lifetime, but it is absolutely impossible to have no friends. Even Robinson Crusoe on a desolate island was badly in need of a "Friday". One cannot choose his or her parents, but except for Robinson, everybody can have the freedom to choose friends. It is true that one's choices should be to one's liking, but it's not always the case. You pick and choose, and at the same time, are picked and chosen by others. Being chosen is an honor, but is may not be a pleasure. There are many who come to press your doorbell, but how many of them can make "go into raptures?" generally speaking, doorbell pressers fall into the following four categories.
第一型，高级而有趣。这种朋友理想是理想，只是可遇而不可求。世界上高级的人很多，有趣的人也很多，又高级又有趣的人却少之又少。高级的人使人尊敬，有趣的人使人欢喜，又高级又有趣的人，使人敬而不畏，亲而不狎，交接愈久，芬芳愈醇。譬如新鲜的水果，不但甘美可口，而且富于营养，可谓一举两得。朋友是自己的镜子。一个人有了这种朋友，自己的境界也低不到哪里去。先生杖履所至，几曾出现过低级而无趣的俗物？
The first category: refined and humorous. Friends of this category are ideal, but they can only be chanced upon rather than be sought after. There are as numerous refined people as there are humorous ones, but how many can you find who are refined as well as humorous? Refined people are respectable, humorous people are loveable, and people who are both refined and humorous are respectable but not awesome, intimate but not improperly familiar. The longer you are with them, the closer you will be, just as the fresh fruit you eat, which is not only delicious but also nutritious: it kills two birds with one stone. Friends are a mirror of one's own self. If one has a friend of this kind, his or her own taste will not be low. How many vulgar and humorless people have you found wherever Su Dongpo, a great genius of the Song Dynasty, went?
第二型，高级而无趣。这种人大概就是古人所谓的诤友，甚至畏友了。这种朋友，有的知识丰富，有的人格高超，有的呢，“品学兼优”像一个模范生，可惜美中不足，都缺乏那么一点儿幽默感，活泼不起来。你总觉得，他身上有那么一个窍没有打通，因此无法豁然恍然，具备充分的现实感。跟他交谈，既不像打球那样，你来我往，此呼彼应，也不像滚雪球那样，把一个有趣的话题愈滚愈大，精力过人的一类，只管自己发球，不管你接不接得住。消极的一类则以逸待劳，难得接你一球两球。无论对手是积极或消极，总之该你捡球，你不捡球，这场球是别想打下去的。这种畏友的遗憾，在于趣味太窄，所以跟你的“接触面”广不起来。天下之大，他从城南到城北来找你的目的，只在讨论“死亡在法国现代小说中的特殊意义”，或是“爱斯基摩人对性生活的态度”。为这种畏友捡一晚上的球，疲劳是可以想见的。这样的友谊有点像吃药，太苦了一点。
The second category: refined but humorless. These people are virtually zhengyou (friends who will give forthright admonition) or even weiyou (friends with stern moral integrity), as defined by people of olden times. Of these friends, some are with profound knowledge, some with noble character, and still some with "both character and knowledge" like a good model student. The pity is that these people have little sense of humor, seldom lively. You are always feeling that there is something missing in him or her, so it is impossible for you feel that something suddenly dawns on him or her, or to have the necessary sense of reality. Your chat with that person is not like playing basketball with the ball coming and going frequently between the players; neither is it like snowballing, getting the ball larger with each rolling. People who are extremely active only care about their serving of the ball, without considering whether you could get it or not. But the passive people are just the opposite, as they would be idle instead of being hardworking, and they seldom catch your ball. Whether they are active or passive, it is you who should always pick up the ball, and if you don't pick the ball up, the match will be very unlikely to go on. The pity of these friends with stern moral integrity is that their scope of interest is too narrow, and therefore, you cannot have a "wider contact" with them. The world is so big, but the sole purpose of his coming to you from one end of the city to the other is to discuss "the special significance of death in modern French novels", or "the attitude of the Eskimos towards sexual life". You can imagine how tiresome it is to pick up the ball the whole night for these friends. And friendship of this kind is something like taking medicine, which is a bit too bitter.
第三型，低级而有趣。这种朋友极富娱乐价值，说笑话，他最黄；说故事，他最像；消息，他最灵通；关系，他最广阔；好去处，他都去过；坏主意，他都打过。世界上任何话题他都接得下去，至于怎么接法，就不用你操心了。他的全部学问，就在不让外行人听出他没有学问。至于内行人，世界上有多少内行人呢？所以他的马脚在许多客厅和餐厅里跑来跑去，并不怎么露眼。这种人最会说话，餐桌上有了他，一定宾主尽欢，大家喝进去的美酒还不如听进去的美言那么“沁人心脾”。会议上有了他，再空洞的会议也会显得主题正确，内容充沛，没有白开。如果说，第二型的朋友拥有世界上全部的学问，独缺常识，这一型的朋友则恰恰相反，拥有世界上全部的常识，独缺学问。照说低级的人而有趣味，岂非低级趣味，你竟能与他同乐，岂非也有低级趣味之嫌？不过人性是广阔的，谁能保证自己毫无此种不良的成分呢？如果要你做鲁滨逊，你会选第三型还是第二型的朋友做“礼拜五”呢？
The third category: vulgar but humorous. Friends of this type are highly amusing. When joking, they will offer you the obscenest; when telling stories, theirs will be the most vivid; when talking about rumors, they are the best-informed; when socializing, they are the most popular; they have been to all good places and they have nurtured all evil thoughts. There is no topic that they cannot say something about, but how they manage to do this is none of your business. Their learning lies in the way that no laymen will find that they are not knowledgeable. As to those who are adept …, but how many adept people have seen in this world? That is why they can be active in the living room and the restaurant without letting the cat out of the bag. These people have glib tongue, and if dining with others, both the host and the guests will be happy. What goes into the ear is much better than what goes into the mouth. If they were in a meeting, a least meaningful meeting would seem to be the most significant, full of content and instructive. If the second category of people possess all the learning in the world but common sense, people of this category are just the other way round: they possess all the common sense of the world but no true learning. In the ordinary course of events, if vulgar people are humorous, their humor would be vulgar, so how can you share pleasure with them? Or are you yourself vulgarly humorous? No. Human nature is heterogeneous. Who can pledge that you yourself are completely void of this unhealthy element? If you wanted to be Robinson, which "Friday" would you like to choose, from the third category or from the second?
第四型，低级而无趣。这种朋友，跟第一型的朋友一样少，或然率相当之低。这种人当然自有一套价值标准，非但不会承认自己低级而无趣。恐怕还自以为又高级又有趣呢？然则，余不欲与之同乐矣。
The fourth category: vulgar and humorless. Friends of this type are as few as those of the first type, and the chances of meeting them are slim. These people certainly have a set of principles of valuing things. Most likely they will not admit that they are vulgar and humorless, instead they will think that they are refined and humorous. However, they are not the type of people that I will share pleasure with.