Full Idea
I have demonstrated that whatever moves is continuously created and that bodies are nothing at any time between the instants in motion.
Gist of Idea
Bodies are recreated in motion, and don't exist in intervening instants
Source
Gottfried Leibniz (Letters to Thomasius [1669], 1669.04), quoted by Daniel Garber - Leibniz:Body,Substance,Monad 1
Book Reference
Garber,Daniel: 'Leibniz: Body, Substance, Monad' [OUP 2009], p.30
A Reaction
Leibniz is a little over-confident about what he has 'demonstrated', but I think (from this remark) that he would not have been displeased with quantum theory, and the notion of a 'quantum leap' and a 'Planck time'. A 'conatus' is a 'smallest motion'.