s more anxious not to put a man in prison for stealing unless he is actually wicked； than it is not to hang him for killing another？ That can hardly be。 The true answer is； that the intent is an index to the external event which probably would have happened； and that； if the law is to punish at all； it must； in this case； go on probabilities； not on accomplished facts。 The analogy to the manner of dealing with attempts is plain。 Theft may be called an attempt to permanently deprive a man of his property； which is punished with the same severity whether successful or not。 If theft can rightly be considered in this way； intent must play the same part as in other attempts。 An act which does not fully accomplish the prohibited result may be made wrongful by evidence that but for some interference it would have been followed by other acts co…ordinated with it to produce that result。 This can only be shown by showing intent。 In theft the intent to deprive the owner of his property establishes that the thief would have retained； or would not have taken steps to restore； the stolen goods。 Nor would it matter that the thief afterwards changed his mind and returned the goods。 From the point of view of attempt； the crime was already complete when the property was carried off。
It may be objected to this view； that； if intent is only a makeshift which from a practical necessity takes the place of actual deprivation； it ought not to be required where the actual deprivation is wholly accomplished； provided the same criminal act produces the whole effect。 Suppose； for instance； that by one and the same motion a man seizes and backs another's horse over a precipice。 The whole evil which the law seeks to prevent is the natural and manifestly ＇73＇ certain consequence of the act under the known circumstances。 In such a case； if the law of larceny is consistent with the theories here maintained； the act should be passed upon according to its tendency； and the actual intent of the wrong…doer not in any way considered。 Yet it is possible； to say the least； that even in such a case the intent would make all the difference。 I assume that the act was without excuse and wrongful； and that it would have amounted to larceny； if done for the purpose of depriving the owner of his horse。 Nevertheless； if it was done for the sake of an experiment； and without actual foresight of the destruction； or evil design against the owner； the trespasser might not be held a thief。
The inconsistency； if there is one； seems to be explained by the way in which the law has grown。 The distinctions of the common law as to theft are not those of a broad theory of legislation； they are highly technical； and very largely dependent upon history for explanation。 /1/
The type of theft is taking to one's own user It used to be； and sometimes still is； thought that the taking must be lucri catesa； for the sake of some advantage to the thief。 In such cases the owner is deprived of his property by the thief's keeping it； not by its destruction； and the permanence of his loss can only be judged of beforehand by the intent to keep。 The intent is therefore always necessary； and it is naturally stated in the form of a self…regarding intent。 It was an advance on the old precedents when it was decided that the intent to deprive the owner of his property was sufficient。 As late as 1815 the English judges stood only six to five in favor of the proposition ＇74＇ that it was larceny to take a horse intending to kill it for no other purpose than to destroy evidence against a friend。 /1/ Even that case； however； did not do away with the universality of intent as a test； for the destruction followed the taking； and it is an ancient rule that the criminality of the act must be determined by the state of things at the time of the taking； and not afterwards。 Whether the law of larceny would follow what seems to be the general principle of criminal law； or would be held back by tradition； could only be decided by a case like that supposed above； where the same act accomplishes both taking and destruction。 As has been suggested already； tradition might very possibly prevail。
Another crime in which the peculiarities noticed in larceny are still more clearly marked； and at the same time more easily explained； is burglary。 It is defined as breaking and entering any dwelling…house by night with intent to commit a felony therein。 /2/ The object of punishing such a breaking and entering is not to prevent trespasses； even when committed by night； but only such trespasses as are the first step to wrongs of a greater magnitude； like robbery or murder。 /3/ In this case the function of intent when proved appears more clearly than in theft； but it is precisely similar。 It is an index to the probability of certain future acts which the law seeks to prevent。 And here the law gives evidence that this is the true explanation。 For if the apprehended act did follow； then it is no longer necessary to allege that the breaking and entering was with that intent。 An indictment for burglary which charges that ＇75＇ the defendant broke into a dwelling…house and stole certain property； is just as good as one which alleges that he broke in with intent to steal。 /1/
It is believed that enough has now been said to explain the general theory of criminal liability； as it stands at common law。 The result may be summed up as follows。 All acts are indifferent per se。
In the characteristic type of substantive crime acts are rendered criminal because they are done finder circumstances in which they will probably cause some harm which the law seeks to prevent。
The test of criminality in such cases is the degree of danger shown by experience to attend that act under those circumstances。
In such cases the mens rea； or actual wickedness of the party； is wholly unnecessary； and all reference to the state of his consciousness is misleading if it means anything more than that the circumstances in connection with which the tendency of his act is judged are the circumstances known to him。 Even the requirement of knowledge is subject to certain limitations。 A man must find out at his peril things which a reasonable and prudent man would have inferred from the things actually known。 In some cases； especially of statutory crimes； he must go even further； and； when he knows certain facts； must find out at his peril whether the other facts are present which would make the act criminal。 A man who abducts a girl from her parents in England must find out at his peril whether she is under sixteen。
＇76＇ In some cases it may be that the consequence of the act； under the circumstances； must be actually foreseen； if it is a consequence which a prudent man would not have foreseen。 The reference to the prudent man； as a standard； is the only form in which blameworthiness as such is an element of crime； and what would be blameworthy in such a man is an element；first； as a survival of true moral standards； second； because to punish what would not be blameworthy in an average member of the community would be to enforce a standard which was indefensible theoretically； and which practically was too high for that community。
In some cases； actual malice or intent； in the common meaning of those words； is an element in crime。 But it will be found that； when it is so； it is because the act when done maliciously is followed by harm which would not have followed the act alone； or because the intent raises a strong probability that ail act； innocent in itself； will be followed by other acts or events in connection with which it will accomplish the result sought to be prevented by the law。
LECTURE III。
TORTS。 TRESPASS AND NEGLIGENCE。
The object of the next two Lectures is to discover whether there is any common ground at the bottom of all liability in tort； and if so； what that ground is。 Supposing the attempt to succeed； it will reveal the general principle of civil liability at common law。 The liabilities incurred by way of contract are more or less expressly fixed by the agreement of the parties concerned； but those arising from a tort are independent of any previous consent of the wrong…doer to bear the loss occasioned by his act。 If A fails to pay a certain sum on a certain day； or to deliver a lecture on a certain night； after having made a binding promise to do so； the damages which he has to pay are recovered in accordance with his consent that some or all of the harms which may be caused by his failure shall fall upon him。 But when A assaults or slanders his neighbor； or converts his neighbor's property； he does a harm which he has never consented to bear； and if the law makes him pay for it； the reason for doing so must be found in some general view of the conduct which every one may fairly expect and demand from every other； whether that other has agreed to it or not。
Such a general view is very hard to find。 The law did not begin with a theory。 It has never worked one out。 The point from which it started and that at which I shall ＇78＇ try to show that it has arrived； are on different planes。 In the progress from one to the other； it is to be expected that its course should not be straight and its direction not always visible。 All that can be done is to point out a tendency； and to justify it。 The tendency； which is our main concern； is a matter of fact to be gathered from the cases。 But the difficulty of showing it is much enhanced by the circumstance that； until lately； the substantive law has been approached only through the categories of the forms of action。 Discussions of legislative principle have been darkened by arguments on the limits between trespass and case； or on the scope of a general issue。 In place of a theory of tort； we have a theory of trespass。 And even within that narrower limit； precedents of the time of the assize and jurata have been applied without a thought of their connection with a long forgotten
procedure。
Since the ancient forms of action have disappeared； a broader treatment of the subject ought to be possible。 Ignorance is the best of law reformers。 People are glad to discuss a question on general principles； when they have forgotten the special knowledge necessary for technical reasoning。 But the pres