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Imagine a circle that contains all of human knowledge:
![](http://208.109.218.43/matt.might.net/articles/phd-school-in-pictures/images/PhDKnowledge.001.jpg)
By the time you finish elementary school, you know a little:
![](http://208.109.218.43/matt.might.net/articles/phd-school-in-pictures/images/PhDKnowledge.002.jpg)
By the time you finish high school, you know a bit more:
![](http://208.109.218.43/matt.might.net/articles/phd-school-in-pictures/images/PhDKnowledge.003.jpg)
With a bachelor's degree, you gain a specialty:
![](http://208.109.218.43/matt.might.net/articles/phd-school-in-pictures/images/PhDKnowledge.004.jpg)
A master's degree deepens that specialty:
![](http://208.109.218.43/matt.might.net/articles/phd-school-in-pictures/images/PhDKnowledge.005.jpg)
Reading research papers takes you to the edge of human knowledge:
![](http://208.109.218.43/matt.might.net/articles/phd-school-in-pictures/images/PhDKnowledge.006.jpg)
Once you're at the boundary, you focus:
![](http://208.109.218.43/matt.might.net/articles/phd-school-in-pictures/images/PhDKnowledge.007.jpg)
You push at the boundary for a few years:
![](http://208.109.218.43/matt.might.net/articles/phd-school-in-pictures/images/PhDKnowledge.008.jpg)
Until one day, the boundary gives way:
![](http://208.109.218.43/matt.might.net/articles/phd-school-in-pictures/images/PhDKnowledge.009.jpg)
And, that dent you've made is called a Ph.D.:
![](http://208.109.218.43/matt.might.net/articles/phd-school-in-pictures/images/PhDKnowledge.010.jpg)
Of course, the world looks different to you now:
![](http://208.109.218.43/matt.might.net/articles/phd-school-in-pictures/images/PhDKnowledge.011.jpg)
So, don't forget the bigger picture:
![](http://208.109.218.43/matt.might.net/articles/phd-school-in-pictures/images/PhDKnowledge.012.jpg)
Keep pushing.