By G. W. Leibniz - Discourse on Metaphysics and Other Essays: On The Ultimate Origination of Things, Preface to the New Essays, The Monadology Paperback – January 1, 1636

Leibniz monadology was considered inferior Newton's mechanical universe. However, 350 years later we find that Leibniz's criticisms of Newtonian physics were in fact correct. We find that Leibniz was much closer to the truth than Newton was.

For kindle version, get the “philosophical essays” instead. It’s $1 more, but gives way more content.

It's a great collection of crucial Leibniz texts