"Anyone who stops learning is old, whether at twenty or eighty. Anyone who keeps learning stays young.
"The greatest thing in life is to keep your mind young."
"The trouble is that no one wants to correct himself and everyone meddles at correcting others: thus everything stays as it is."
--San Pedro of Alcantara.
"The things I want to know are in books. My best friend is the man who will get me a book I haven't read."