To understand a rule governing conduct towards others, even to discover it for oneself and to express it neatly, is easy enough; and still, very soon afterwards, the rule may be broken in practice. But that is no reason for despair; and you need not fancy that as it is impossible to regulate your life in accordance with abstract ideas and maxims, it is better to live just as you please. Here, as in all theoretical instruction that aims at a practical result, the first thing to do is to understand the rule; the second thing is to learn the practice of it. The theory may be understand at once by an effort of reason, and yet the practice of it acquired only in course of time. A pupil may lean the various notes on an instrument of music, or the different position in fencing; and when he makes a mistake, as he is sure to do, however hard he tries, he is apt to think it will be impossible to observe the rules, when he is set to read music at sight or challenged to a furious duel. But for all that, gradual practice makes him perfect, through a long series of slips, blunders and fresh efforts. It is just the same in other things; in learning to write and speak Latin, a man will forget the grammatical rules; it is only by long practice that a blockhead turns into a courtier, that a passionate man becomes shrewd and worldly-wise, or a frank person reserved, or a noble person ironical. But though self-discipline of this kind is the result of long habit, it always works by a sort of external compulsion, which Nature never ceases to resist and sometimes unexpectedly overcomes. The difference between action in accordance with abstract principles, and action as the result of original, innate tendency, is the same as that between a work of art, say a watch--where form and movement are impressed upon shapeless and inert matter--and a living organism, where form and matter are one, and each is inseparable from the other. There is a maxim attributed to the Emperor Napoleon, which expresses this relation between acquired and innate character, and confirms what I have said: _everything that is unnatural is imperfect_;--a rule of universal application, whether in the physical or in the moral sphere. The only exception I can think of to this rule is aventurine,[1] a substance known to mineralogists, which in its natural state cannot compare with the artificial preparation of it. [Footnote 1: _Translator's Note_. Aventurine is a rare kind of quartz; and the same name is given to a brownish-colored glass much resembling it, which is manufactured at Murano. It is so called from the fact that the glass was discovered by chance _(arventura)_.]