Full Idea
It is not necessary that a machine be perfect, in order to show with what design it was made.
Gist of Idea
Even an imperfect machine can exhibit obvious design
Source
William Paley (Natural Theology [1802], Ch 1)
Book Reference
'The Existence of God', ed/tr. Hick,John [Macmillan 1964], p.101
A Reaction
This encounters Hume's point that you will then have to infer that the designer contains similar imperfections. If you look at plagues, famines and mothers dying in childbirth (see Mill), you might wish the designer had never started.