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. . . .
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. . . .
79 The business of the law of torts is to fix the dividing lines between those cases in which a man is liable for harm which he has done, and those in which he is not. But it cannot enable him to predict with certainty whether a given act under given circumstances will make him liable, because an act will rarely have that effect unless followed by damage, and for the most part, if not always, the consequences of an act are not known, but only guessed at as more or less probable. All the rules that the law can lay down beforehand are rules for determining the conduct which will be followed by liability if it is followed by harm—that is, the conduct which a man pursues at his peril. The only guide for the future to be drawn from a decision against a defendant in an action of tort is that similar acts, under circumstances which cannot be distinguished except by the result from those of the defendant, are done at the peril of the actor; that if he escapes liability, it is simply because by good fortune no harm comes of his conduct in the particular event.
If, therefore, there is any common ground for all liability in tort, we shall best find it by eliminating the event as it actually turns out, and by considering only the principles on which the peril of his conduct is thrown upon the actor. We are to ask what are the elements, on the defendant's side, which must all be present before liability is possible, and the presence of which will commonly make him liable if damage follows.
The law of torts abounds in moral phraseology. It has much to say of wrongs, of malice, fraud, intent, and negligence. Hence it may naturally be supposed that the risk of a man's conduct is thrown upon him as the result of some moral short-coming. But while this notion has been 80 entertained, the extreme opposite will be found to have been a far more popular opinion;—I mean the notion that a man is answerable for all the consequences of his acts, or, in other words, that he acts at his peril always, and wholly irrespective of the state of his consciousness upon the matter. . . .
The general principle of our law is that loss from accident must lie where it falls, and this principle is not affected by the fact that a human being is the instrument of misfortune. . . . In the language of the late Chief Justice Nelson of New York: "No case or principle can be found, or if found can be maintained, subjecting an individual to liability for 95 an act done without fault on his part.... All the cases concede that an injury arising from inevitable accident, or, which in law or reason is the same thing, from an act that ordinary human care and foresight are unable to guard against, is but the misfortune of the sufferer, and lays no foundation for legal responsibility." If this were not so, any act would be sufficient, however remote, which set in motion or opened the door for a series of physical sequences ending in damage; such as riding the horse, in the case of the runaway, or even coming to a place where one is seized with a fit and strikes the plaintiff in an unconscious spasm. Nay, why need the defendant have acted at all, and why is it not enough that his existence has been at the expense of the plaintiff? The requirement of an act is the requirement that the defendant should have made a choice. But the only possible purpose of introducing this moral element is to make the power of avoiding the evil complained of a condition of liability. . . .
A man need not, it is true, do this or that act, the term act implies a choice,—but he must act somehow. Furthermore, the public generally profits by individual activity. As action cannot be avoided, and tends to the public good, there is obviously no policy in throwing the hazard of what is at once desirable and inevitable upon the actor. 96 The state might conceivably make itself a mutual insurance company against accidents, and distribute the burden of its citizens' mishaps among all its members. There might be a pension for paralytics, and state aid for those who suffered in person or estate from tempest or wild beasts. As between individuals it might adopt the mutual insurance principle . . . or it might throw all loss upon the actor irrespective of fault. The state does none of these things, however, and the prevailing view is that its cumbrous and expensive machinery ought not to be set in motion unless some clear benefit is to be derived from disturbing the status quo. State interference is an evil, where it cannot be shown to be a good. Universal insurance, if desired, can be better and more cheaply accomplished by private enterprise. The undertaking to redistribute losses simply on the ground that they resulted from the defendant's act would not only be open to these objections, but, as it is hoped the preceding discussion has shown, to the still graver one of offending the sense of justice. Unless my act is of a nature to threaten others, unless under the circumstances a prudent man would have foreseen the possibility of harm, it is no more justifiable to make me indemnify my neighbor against the consequences, than to make me do the same thing if I had fallen upon him in a fit, or to compel me to insure him against lightning. . . .
Supposing it now to be conceded that the general notion upon which liability to an action is founded is fault or blameworthiness in some sense, the question arises, whether it is so in the sense of personal moral shortcoming . . . . Suppose that a defendant were allowed to testify that, before acting, he considered carefully what would be the conduct of a prudent man under the circumstances, and, having formed the best judgment he could, acted accordingly. If the story was believed, it would be conclusive against the defendant's negligence judged by a moral standard which would take his personal characteristics into account. But supposing any such evidence to have got before the jury, it is very clear that the court would say, Gentlemen, the question is not whether the defendant thought his conduct was that of a prudent man, but whether you think it was. . . .
108 The standards of the law are standards of general application. The law takes no account of the infinite varieties of temperament, intellect, and education which make the internal character of a given act so different in different men. It does not attempt to see men as God sees them, for more than one sufficient reason. In the first place, the impossibility of nicely measuring a man's powers and limitations is far clearer than that of ascertaining his knowledge of law, which has been thought to account for what is called the presumption that every man knows the law. But a more satisfactory explanation is, that, when men live in society, a certain average of conduct, a sacrifice of individual peculiarities going beyond a certain point, is necessary to the general welfare. If, for instance, a man is born hasty and awkward, is always having accidents and hurting himself or his neighbors, no doubt his congenital defects will be allowed for in the courts of Heaven, but his slips are no less troublesome to his neighbors than if they sprang from guilty neglect. His neighbors accordingly require him, at his proper peril, to come up to their standard, and the courts which they establish decline to take his personal equation into account.
The rule that the law does, in general, determine liability by blameworthiness, is subject to the limitation that minute differences of character are not allowed for. The law considers, in other words, what would be blameworthy in the average man, the man of ordinary intelligence and prudence, and determines liability by that. If we fall below the level in those gifts, it is our misfortune; so much as that we must have at our peril, for the reasons just given. . . .
There are exceptions to the principle that every man is presumed to possess ordinary capacity to avoid harm to his neighbors, which illustrate the rule, and also the moral basis of liability in general. When a man has a distinct defect of such a nature that all can recognize it as making certain precautions impossible, he will not be held answerable for not taking them. A blind man is not required to see at his peril; and although he is, no doubt, bound to consider his infirmity in regulating his actions, yet if he properly finds himself in a certain situation, the neglect of precautions requiring eyesight would not prevent his recovering for an injury to himself, and, it may be presumed, would not make him liable for injuring another. So it is held that, in cases where he is the plaintiff, an infant of very tender years is only bound to take the precautions of which an infant is capable; the same principle may be cautiously applied where he is defendant. . . .
Taking the qualification last established in connection with the general proposition previously laid down, it will  now be assumed that, on the one hand, the law presumes or requires a man to possess ordinary capacity to avoid harming his neighbors, unless a clear and manifest incapacity be shown; but that, on the other, it does not in general hold him liable for unintentional injury, unless, possessing such capacity, he might and ought to have foreseen the danger, or, in other words, unless a man of ordinary intelligence and forethought would have been to blame for acting as he did. The next question is, whether this vague test is all that the law has to say upon the matter, and the same question in another form, by whom this test is to be applied.
Notwithstanding the fact that the grounds of legal liability are moral to the extent above explained, it must be borne in mind that law only works within the sphere of the senses. If the external phenomena, the manifest acts and omissions, are such as it requires, it is wholly indifferent to the internal phenomena of conscience. A man may have as bad a heart as he chooses, if his conduct is within the rules. In other words, the standards of the law are external standards, and, however much it may take moral considerations into account, it does so only for the purpose of drawing a line between such bodily motions and rests as it permits, and such as it does not. What the law really forbids, and the only thing it forbids, is the act on the wrong side of the line, be that act blameworthy or otherwise. . . .
It is not intended that the public force should fall upon an individual accidentally, or at the whim of any body of men. The standard, that is, 111 must be fixed. In practice, no doubt, one man may have to pay and another may escape, according to the different feelings of different juries. But this merely shows that the law does not perfectly accomplish its ends. The theory or intention of the law is not that the feeling of approbation or blame which a particular twelve may entertain should be the criterion. They are supposed to leave their idiosyncrasies on one side, and to represent the feeling of the community. The ideal average prudent man, whose equivalent the jury is taken to be in many cases, and whose culpability or innocence is the supposed test, is a constant, and his conduct under given circumstances is theoretically always the same.
Finally, any legal standard must, in theory, be capable of being known. When a man has to pay damages, he is supposed to have broken the law, and he is further supposed to have known what the law was.
If, now, the ordinary liabilities in tort arise from failure to comply with fixed and uniform standards of external conduct, which every man is presumed and required to know, it is obvious that it ought to be possible, sooner or later, to formulate these standards at least to some extent, and that to do so must at last be the business of the court. It is equally clear that the featureless generality, that the defendant was bound to use such care as a prudent man would do under the circumstances, ought to be continually giving place to the specific one, that he was bound to use this or that precaution under these or those circumstances. The standard which the defendant was bound to come up to was a standard of specific acts or omissions, with reference to the specific circumstances in which he found himself. If in the whole department of 112 unintentional wrongs the courts arrived at no further utterance than the question of negligence, and left every case, without rudder or compass, to the jury, they would simply confess their inability to state a very large part of the law which they required the defendant to know, and would assert, by implication, that nothing could be learned by experience. But neither courts nor legislatures have ever stopped at that point.
From the time of Alfred to the present day, statutes and decisions have busied themselves with defining the precautions to be taken in certain familiar cases; that is, with substituting for the vague test of the care exercised by a prudent man, a precise one of specific acts or omissions. . . .
No doubt the general foundation of legal liability in blameworthiness, as determined by the existing average standards of the community, should always be kept in mind, for the purpose of keeping such concrete rules as from time to time may be laid down conformable to daily life. No doubt this conformity is the practical justification for requiring a man to know the civil law, as the fact that crimes are also generally sins is one of the practical justifications for requiring a man to know the criminal law. . . .
The trouble with many cases of negligence is, that they are of a kind not frequently recurring, so as to enable any given judge to profit by long experience with juries to lay down rules, and that the elements are so complex that courts are glad to leave the whole matter in a lump for the jury's determination.