"The world is a book, and those who do not travel read only one page."

"I have been a fool, but I have learned from my folly."

"The diversity of the phenomena of nature is so great, and the treasures hidden in the heavens so rich, precisely in order that the human mind shall never be lacking in fresh nourishment."

"I have been a man of faith, and I have trusted in God's plan."

"See, I cast the die, and I write the book. Whether it is to be read by the people of the present or of the future makes no difference: let it await its reader for a hundred years, if God himself has s…"