Thinking Vs Memorizing

I'm currently reading John Stuart Mill's autobiography and was surprise to learn that there was a great deal of his youth spent studying many of the classics. This endeavor was the work of his father who paid special attention to the education of his children. What surprised me the most was the fact that John Stuart Mill's father understood the difference between memorizing facts and thinking - he made a point to focus on the later.

Going through this autobiography has made me realized that a great deal of my own self-education was spent merely memorizing facts (just like I was thought to do in school). In-fact, I was reminded of an event that occurred roughly 10 years ago where one of my friends said to me "everything you know comes from a book - you don't think about anything!" Only in recent years have I begun formulating my own thoughts regarding what I'm learning  and it's made me more picky about what to read, or learn about, next.
Obviously, we all need to start somewhere and when we first start on our self-education journey it's mostly going to be about memorizing, what we consider to be, important facts. What helped me move, slowly, away from memorizing to thinking is writing. When I write about something, it forces me to think about it and, over time, you come to realize that a greater deal of your time is spent thinking about what you've learn than only memorizing it.

The real purpose of self-education is to sharpen your thinking - not memorizing facts. The transition between the two can take some time.