Chapter II. is on Justice; defined as the disposition that leads a man, where his own interests or passions are concerned, to act according to the judgment he would form of another man's duty in his situation. He introduces a criticism on Adam Smith, and re-asserts the doctrine of an innate faculty, explained as the power of forming moral ideas, and not as the innate possession of ideas. For the most part, his exposition is didactic and desultory, with occasional discussions of a critical and scientific nature; as, for example, some remarks on Hume's theory that Justice is an artificial virtue, an account of the basis of Jurisprudence, and a few observations on the Right of Property.
In Chapter III., on Veracity, he contends that considerations of utility do not account for the whole force of our approbation of this virtue. [So might any one say that considerations of what money can purchase do not account for the whole strength of avarice].
In Chapter IV. he deals with Duties to ourselves, and occupies the chapter with a dissertation on Happiness. He first gives an account of the theories of the Stoics and the Epicureans, which connect themselves most closely with the problem of Happiness; and next advances some observations of his own on the subject.
His first remark is on the influence of the Temper, by which he means the Resentful or Irascible passion, on Happiness. As against a censorious disposition, he sets up the pleasure of the benevolent sentiments; he enjoins candour with respect to the motives of others, and a devoted attachment to truth and virtue for their intrinsic excellence; and warns us, that the causes that alienate our affections from our fellow-creatures, suggest gloomy and Hamlet-like conceptions of the order of the universe.
He next adverts to the influence of the Imagination on Happiness. On this, he has in view the addition made to our enjoyments or our sufferings by the respective predominance of hope or of fear in the mind. Allowing for constitutional bias, he recognizes, as the two great sources of a desponding imagination, Superstition and Scepticism, whose evils he descants upon at length. He also dwells on the influence of casual associations on happiness, and commends this subject to the care of educators; giving, as an example, the tendency of associations with Greece and Rome to add to the courage of the classically educated soldier.
His third position is the Influence of our Opinions on Happiness. He here quotes, from Ferguson, examples of opinions unfavourable to Happiness; such as these: 'that happiness consists in having nothing to do,' 'that anything is preferable to happiness,' 'that anything can amuse us better than our duties.' He also puts forward as a happy opinion the Stoical view, 'I am in the station that God has assigned me.' [It must be confessed, however, that these prescriptions savour of the Platonic device of inculcating opinions, not because of their truth, but because of their supposed good consequences otherwise: a proceeding scarcely compatible with an Ethical system that proclaims veracity as superior to utility. On such a system, we are prohibited from looking to anything in an opinion but its truth; we are to suffer for truth, and not to cultivate opinions because of their happy results.]
Stewart remarks finally on the influence of the Habits, on which he notices the power of the mind to accommodate itself to circumstances, and copies Paley's observations on the setting of the habits.
In continuation of the subject of Happiness, he presents a classification of our most important pleasures. We give the heads, there being little to detain us in the author's brief illustration of them. I.—The pleasures of Activity and Repose; II.—The pleasures of Sense; III.—The pleasures of the Imagination; IV.—The pleasures of the Understanding; and V.—The pleasures of the Heart, or of the various benevolent affections. He would have added Taste, or Fine Art, but this is confined to a select few.
In a concluding chapter (V.), he sums up the general result of the Ethical enquiry, under the title, 'the Nature and Essence of Virtue.' No observation of any novelty occurs in this chapter. Virtue is doing our duty; the intentions of the agent are to be looked to; the enlightened discharge of our duty often demands an exercise of the Reason to adjudge between conflicting claims; there is a close relationship, not defined, between Ethics and Politics.
The views of Stewart represent, in the chief points, although not in all, the Ethical theory that has found the greatest number of supporters.