Summum bonum is a Latin expression meaning the highest or ultimate good, which was introduced by Cicero to denote the fundamental principle on which some system of ethics is based — that is, the aim of actions, which, if consistently pursued, will lead to the best possible life.
Reason turns out to be the one thing which satisfies all the qualifications previously established-it is a general, subservient, and single ideal and is admirable in itself. Peirce says that "the essence of Reason is such that its being never can have been completely perfected. It always must be in a state of incipiency, of growth' and is like the character of a man, which is in a state of constant flux and develops only as the occasions arise.