知乎 匿名用户
很早以前就有一个老外和我聊过，当时我还没恋爱过，他刚分手，我问他要不要和女友继续做朋友，他很干脆的否定了。然后他给了我一套被称之为”麦当劳外卖定理"的理论，这套理论一直影响我的意识，使得我在自己也面临分手时顶住了巨大的思念与对方断开了联系：

试想你习惯在下班在回家路上的麦当劳买一份外卖带回去吃，你总是习惯要一份套餐，里面的汉堡会让你果腹，而薯条则会满足你手口并用的同时看电视消磨时间的小爱好。你就这样，每天买一份有汉堡和薯条的套餐，甚至连外卖窗口的服务员都深知你的习惯，会见到你就开始很麻利地准备一切——你都用不着和她再说一遍。
这样的生活过了很长一段时间，你甚至都觉得自己一辈子就会这样过了，可是突然有一天服务员给你的纸袋中没有了薯条，你很奇怪于是询问她，她回答说：“噢不，虽然之前看起来理所当然，但是从今以后从原则上来说我不能向你提供薯条了。”
你追问为什么，但是她只是说“就是现在原则上，不能给你薯条了。没有薯条给你了。”
虽然没有答案，但是你马上又安慰自己，不是还有汉堡么，而且汉堡看起来比薯条重要。
于是你仍然每天光顾一样的麦当劳，向一样的服务员买一份外卖——里面不包括薯条。
直到有一天麦当劳生意比往常好，你那天不得不排队购买。而在就要轮到你时，你听到你前面的男人也要了一份一样的套餐。而在他说完自己的order之后你听见那个服务员微笑地对他说：“要不要加一份薯条呢？”

以上。

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-----这可能是我在知乎上唯一一个发布了两年多还能每月都收到赞的答案-----
下面贴上故事的原文，它本身也是一个很冷门的梗。因为最初听这套理论也是朋友转述，所以上面的答案正文会和这个原文有细节上的出入。并且，本答案并非下面英文的翻译。

Imagine if you went to McDonald's a lot and ordered a Big Mac Combo meal. A Big Mac, Large Fries and a Coke. You really like this meal. One day, you PUll up to the drive through and order the Big Mac Combo meal and the girl tells you, "I'm sorry - you can have the Big Mac and the Coke, but you can't get fries with that anymore." You think about this for a moment, and sure - the Big Mac is the centerpiece of the meal, but McDonald's has some really good fries and you like their fries with your meal. So you say, "I've been able to get fries with that before, why can't I have fries with my Big Mac combo anymore?" The girls says, "Well, I just think it is better if you only have the Big Mac and the Coke from here on out."

At this point, a lot of guys are going to go to Wendy's or BK and see if they can get fries with their combo at that drive through window. But there are some guys who REALLY like McDonald's Big Macs and they might think, "If I keep coming here and ordering the Big Mac and Coke, maybe she'll change her mind and give me some fries with that later." So they will keep on getting the combo without the fries until the deal breaker happens: One day that guy is going to order the Big Mac and Coke and then he's going to pull up a little bit to pay, and someone else is going to pull up to the drive through speaker and order the "Big Mac Combo" and he is going to hear the girl say, "Would you like fries with that?"

That's why guys don't like to be friends with a girl who breaks up with them.


http://www.zhihu.com/question/19749415

顶贴是一种美德！