翻译自@mattmight

Every fall, I explain to a fresh batch of Ph.D. students what a Ph.D. is.
It's hard to describe it in words.
So, I use pictures.
Read below for the illustrated guide to a Ph.D.
每年秋季，我都要向新来的博士解释什么是博士。因为很难用语言描述，所以我用图来描述。

Imagine a circle that contains all of human knowledge:
想象一个圆代表了人类所知道的知识：

By the time you finish elementary school, you know a little:
当你从中学毕业时，你懂了一点知识：

By the time you finish high school, you know a bit more:
当时高中毕业时，你懂得了更多知识：

With a bachelor's degree, you gain a specialty:
当你拿到了学士学位的时候，你有一定的专长了：

A master's degree deepens that specialty:
硕士学位让你显得更加专业：

Reading research papers takes you to the edge of human knowledge:
在你读了很多的论文后，你慢慢的来到了人类知识的边缘：

Once you're at the boundary, you focus:
一旦你来到知识的边缘处，你开始把研究重心放在某个点：

You push at the boundary for a few years:
你在这点上奋斗一些年后：

Until one day, the boundary gives way:
直到有一天，你终于突破了：

And, that dent you've made is called a Ph.D.:
然后，你才能被称为博士：

Of course, the world looks different to you now:
在你面前，世界变得不同了：

So, don't forget the bigger picture:
记住，可别忘记整个背景（你只是在某一点上有所作为了）：

Keep pushing.
所以，保持努力。