There are many kinds of knowledge, and it depends on what crowd you happen to be in, or how the fashions of the day happen to run, which kind of knowledge, is most respected at the moment. There are fashions in knowledge, just as there are in everything else. When some of us were lads, knowledge used to be limited to the Bible. There were certain men in the neighbourhood who knew the Book thoroughly, and they were looked up to and respected. Biblical knowledge was highly valued then. But nowadays it is doubtful whether deep acquaintance with the Bible would be sufficient to win a man a name for learning.
Knowledge, to my mind, is something that in the past somebody knew and left in a form which enables all who will to obtain it. If a man is born with normal human faculties, if he is equipped with enough ability to use the tools which we call "letters" in reading or writing, there is no knowledge within the possession of the race that he cannot have—if he wants it! The only reason why every man does not know everything that the human mind has ever learned is that no one has ever yet found it worth while to know that much. Men satisfy their minds more by finding out things for themselves than by heaping together the things which somebody else has found out. You can go out and gather knowledge all your life, and with all your gathering you will not catch up even with your own times. You may fill your head with all the "facts" of all the ages, and your head may be just an overloaded fact-box when you get through. The point is this: Great piles of knowledge in the head are not the same as mental activity. A man may be very learned and very useless. And then again, a man may be unlearned and very useful.
The object of education is not to fill a man's mind with facts; it is to teach him how to use his mind in thinking. And it often happens that a man can think better if he is not hampered by the knowledge of the past.