What is a living book?

Throughout my 15 years of homeschooling, I was very influenced by the educational philosophy of Charlotte Mason. Miss Mason was an English educator at the turn of the 20th century, and she was very passionate about children having the very best of books~books that would awaken wonder, and inspire a quest to learn more. She spoke of textbooks being like dry sawdust, compared to books filled with ideas, which she called “living books”~books alive with ideas to furnish and nourish growing minds.
”Give your child a single valuable idea, and you have done more for his education that if you had laid upon his mind the burden of bushels of information.“~Charlotte Mason. What a wonderful source of vigorous ideas is the kingdom of books! 
Do you remember the name of the single textbook that you had in school? Neither do I! But I can tell you about the wonderful stories that I read, stories that I still recall with delight today, and would STILL enjoy reading. (Which is another “living book” tip off~these books are generational!;) 
There is not a single subject that cannot be taught or greatly enhanced with the use of living books: we have exciting historical fiction, beautifully written biographies, books about nature that are written by naturalists who LOVE to share their knowledge of the natural world, poetry to inspire beautiful thoughts, and more! Just as parents would not give children carefully distilled vitamins instead of a variety of wholesome foods; we reject dry textbooks and replace them with books that are ALIVE with ideas. 
To quote the character Kathleen Kelly, in the movie You’ve got Mail, “When you read a book as a child, it becomes a part of your identity in a way that no other reading in your whole life does.” 

A living book is filled with living ideas! And a mind NEEDS ideas in order to grow, in childhood, and in adulthood. “The intellectual life, like every manner of spiritual life, has but one food whereby it lives and grows – the sustenance of living ideas. It is not possible to repeat this too often or too emphatically.” (Charlotte Mason, Vol.3, p.121) 

I will strive to fill this space with books that are valuable for their ideas. Life is too short to eat sawdust!