But even in limiting himself to the individual human nature as it is developed in particular persons, regarding society only as it is incidental to that, even in putting down his new scientific platform of the good that the appetite and will of man naturally seeks, and in marking out scientifically its _degrees_ and _kinds_, he gives us an opportunity to perceive in passing, that he is not altogether without occasion for the use of that particular art, with its peculiar 'organs' and 'methods' and 'illustration,' which he recommends under so many heads in his treatise on that subject, for the delivery or tradition of knowledges, which tend to _innovation_ and _advancement_--knowledge which is 'progressive' and 'foreign from opinions received.' This doctrine of _duty_ is sub-divided into two parts; the _common_ duty of every man as a MAN, or A MEMBER of A STATE, which is that part of the platform and exemplar of good, he has before reported as 'extant, and well laboured.' The other is the _respective_ or _special_ duty of every man in his PROFESSION, VOCATION and PLACE; and it is under this head of the _special_ and _respective_ duties of places, vocations and professions, where the subject begins to grow narrow and pointed, where it assumes immediately, the most critical aspects,--it is here that his new arts of delivery and tradition come in to such good purpose, and stand him instead of other weapons. For this is one of those cases precisely, which the philosopher on the Mountain alluded to, where an argument is set on foot at the table of a man of prodigious fortune, when the man himself is present. Nowhere, perhaps,--in his freest forms of writing, does he give a better reason, for that so deliberate and settled determination, which he so openly declares, and everywhere so stedfastly manifests, not to put himself in an antagonistic attitude towards opinions, and vocations, and professions, as they stood authorized in his time. Nowhere does he venture on a more striking comparison or simile, for the purpose of setting forth that point vividly, and impressing it on the imagination of the reader.