If I had stayed for other people to make my tools and things for me, I had never made anything.

This first appears in the Isaac Newton : A Biography (1934), citing unpublished papers by John Conduitt reporting an anecdote of an occasion where Conduitt asked Newton where he obtained the tools to make his reflecting telescope. Newton is said to have laughed and replied, "If I had stayed for other people to make my tools and things for me I had never made anything of it."