I think the definition of a book is changing.

Make it a rule never to give a child a book you would not read yourself.

A multitude of books distracts the mind.

Books are infinite in number and time is short. The secret of knowledge is to take what is essential. Take that and try to live up to it.

Writing a long and substantial book is like having a friend and companion at your side, to whom you can always turn for comfort and amusement, and whose society becomes more attractive as a new and widening field of interest is lighted in the mind.

Writing a book is an adventure. To begin with it is a toy and an amusement. Then it becomes a mistress, then it becomes a master, then it becomes a tyrant. The last phase is that just as you are about to be reconciled to your servitude, you kill the monster and fling him to the public.