Doctrine of the passions explained and improved, or, A brief and comprehensive scheme of the natural affections of mankind attempted in a plain and easy method, with an account of their names, nature, appearances, effects, and different uses in human This book, "Doctrine of the passions explained and improved or, A brief and comprehensive scheme of the natural affections of mankind," by Isaac Watts, is a replication of a book originally published before 1770. It has been restored by human beings, page by page, so that you may enjoy it in a form as close to the original as possible.