Notice about the Notes
I have added some notes to this work after my lazy practice of working in fits and starts. These notes sometimes stray so wide of the subject that they are not good to read together with the text. I therefore cast them to the end of the Discourse, in which I tried my best to follow the straightest road. Those who will have the courage to start over again can amuse themselves the second time by beating the bushes, and trying to peruse the notes; there will be little harm in the others’ not reading them at all.