Where virtue is, sensibility is the ornament and becoming attire of virtue. On certain occasions it may almost be said to become virtue. But sensibility and all the amiable qualities may likewise become, and too often have become, the panders of vice and the instruments of seduction.
Our virtues are voluntary (and in fact we are in a sense ourselves partly the cause of our moral dispositions, and it is our having a certain character that makes us set up an end of a certain kind), it follows that our vices are voluntary also; they are voluntary in the same manner as our virtues.
For as the interposition of a rivulet, however small, will occasion the line of the phalanx to fluctuate, so any trifling disagreement will be the cause of seditions; but they will not so soon flow from anything else as from the disagreement between virtue and vice, and next to that between poverty and riches.
Certainly virtue is like precious odors, most fragrant when they are incensed, or crushed: for prosperity doth best discover vice, but adversity doth best discover virtue.