A curious soul begins by trying to know everything that it sees, that it comes in contact with. What it wants to know first is the name of an object, what it is called, what it is for, what it is, what it is used for, how to use it, how it is made, how to make the best of a thing, how to profit by it to the utmost. This knowledge is what we call learning. The different divisions of learning, called by different names, are the classification of this knowledge which one gains by study of the outside world. But life is so short and the field of this knowledge is so vast, that a person may go on and on studying. He may perhaps study one branch of knowledge, and he may find that even one life is not sufficient to be fully acquainted with that one particular branch of knowledge.