But, further, the questions as to the relations between the two codes arise in various directions. It is obvious that the criminal law has to employ very rough and ready methods. It cannot estimate, with any accuracy, the degree of immorality implied by any given action. It cannot, and it does not attempt to, look closely into the secrets of a man's heart. It cannot inquire, as a rule, how far a man's crime is the result of bad education or bad surroundings; how far it implies thorough corruption or only superficial faults of temper, or a misunderstanding of some fact or doctrine. It cannot take into account a number of metaphysical or psychological considerations which are connected with the theory of moral responsibility. To settle such points you would have to empanel a jury of philosophers, and the only thing of which you could be certain would be, that such a jury would never agree upon a verdict. Again, there are whole classes of virtues and vices with which the criminal law is not concerned. Ingratitude, to take the common example, is a grave vice, but one which it would be absurd to punish legally. Not only would such an attempt involve impossible inquiries, but the attempt would be self-defeating. If the duty of gratitude to a benefactor were turned into a legal obligation, gratitude proper would cease to exist. To confer a benefit would be the same thing as to acquire a right to repayment. A man who allows his best friend to starve, or to go to the workhouse, may be, morally, far worse than a thief; but you could not punish him legally, without adopting a principle which, even if practicable, would, so far as it operated, be destructive of all disinterested friendship. The law, again, can deal only with criminals who are found out. What proportion they may bear to the whole class of moral offenders is not discoverable; but it is, at least, safe to say that, for every man whom you convict of a crime, you must leave unpunished, because undetected, another sinner who is equally deserving of punishment. And, finally, it is apparently impossible to say, upon any intelligible grounds, what should be the proportion between crime and punishment. How many years' imprisonment does a man deserve for putting out his neighbour's eye? I do not see how such a rule of three can be stated. The good old theory of an eye for an eye and a tooth for a tooth, seems to suggest a possible criterion. But it was difficult to carry out. Deloraine, in the _Lay of the Last Minstrel_, has, as he points out, killed Musgrove's brother; but, on the other hand, Musgrove has killed Deloraine's nephew, and, besides, got a thousand marks ransom out of Deloraine himself. Is the account to be regarded as accurately balanced? Is one brother just equal to a nephew plus a thousand marks? The theory, of course, is an application of an inappropriate analogy. If we regard crime simply as a case of private injury, we may say that it