Self Education

In his book, Man - The Dwelling Place of God, A.W. Tozer (a self-taught man himself) has a chapter on self-education where he lists intellectual activities in the order of their importance:

Thinking 

Observation

Reading

Conversation may once have been part of this list but Tozer made the comment that conversation today is mostly sterile. He was writing over fifty years ago and it made me wonder what he'd think if he was alive now and could listen in on the average adult conversation.

I believe that pure thinking will do more to educate a man than any other activity he can engage in. To afford sympathetic entertainment to abstract ideas, to let one idea beget another, and that another, till the mind teems with them; to compare one idea with others, to weigh, to consider, evaluate, approve, reject, correct, refine; to join thought with thought like an architect till a noble edifice has been created within the mind...
and all this without so much as moving from our chair or opening the eyes - this is to soar above all the lower creation and to come near to the angels of God.

Of all earth's creatures only man can think in this way. And while thinking is the mightiest act a man can perform, perhaps for the very reason that it is the mightiest, it is the one act he likes the least and avoids most.

To think without a proper amount of good reading is to limit our thinking to our own tiny plot of ground. The crop cannot be large. To observe only and neglect reading is to deny ourselves the immense value of other people's observations...

Extensive reading without the discipline of practical observation will lead to bookishness and artificiality. Reading and observing without a great deal of meditating will fill the mind with learned lumber that will always remain alien to us. Knowledge to be our own must be digested by thinking. 

Charlotte Mason wrote something that ties in well with Tozer's observations. She suggests that before turning off your light that you read:

...a leading article from a newspaper, say, or a chapter from Boswell or Jane Austen, or one of Lamb's Essays...

Then narrate silently what you've read...

[You] will not be satisfied with the result but [you] will find that in the act of narrating every power of [your]  mind comes into play, that points and bearings which [you] had not observed are brought out; that the whole is visualized and brought into relief in an extraordinary way; in fact, that scene or argument has become a part of [your] personal experience...

You know - you have thought and made observations.
You have assimilated what you've read.
The knowledge has been digested.