Negligence, in law, primarily the want of care, caution, attention, diligence, skill, or discretion in the performance of an act by one having no positive intention to injure; and secondarily the omission to perform a duty imposed by law for the avoidance of injury to persons or property of others. In the civil law negligence is classed as slight, ordinary, and gross; the first being the want of great care and diligence, the second the want of ordinary care and diligence, and the last the want of even slight care and diligence. The propriety of this classification has often been denied by common law judges; but as the degree of care, caution, and diligence required of parties is different under different circumstances, so that the same want of caution and prudence which under one set of circumstances would render the parties chargeable with it liable as for negligence, would give no right of action under another, the classification is found useful as indicating the different degrees of diligence required by the law in different cases.

Thus, if for the mere accommodation of my neighbor I loan to him the use of my horse, for which he is to make no compensation, it is reasonable that he should take the highest care of him, and that he should respond to me for any damages occasioned by even a slight want of care and diligence; while, on the other hand, if I desire him to keep my horse for me a short time, without compensation and solely for my accommodation, it would be unreasonable to charge him with an obligation for the like extreme care, or to hold him responsible for anything short of serious and culpable neglect. If, however, the bailment is for the mutual accommodation and benefit of both parties, so that he has the use of the horse while I am compensated for it, the just rule would seem to be that he should take such care of the horse as a prudent man would of his own, and that anything short of this, resulting in injury, should be accounted actionable negligence. The rules on this subject have been explained to some extent in the article Bailment, and the liability of an employer for the negligence of his servant is stated in that on Master and Servant. In general, any person guilty of negligence in the exercise of his rights, or failing in due time and manner or with due care to perform a duty, whereby another person sustains injury, is responsible to the party injured for the consequent damage.

Thus, if an attorney undertakes the management of a suit, but neglects to file pleadings in due time, or to attend at the time fixed for trial, or to produce in evidence the documents in his possession proving his client's right, and his client loses his suit in consequence, the injured party by the proper action, counting on this negligence, may recover compensation for what he has suffered thereby; and if a railway company, owing a duty to the public to propel its trains with caution and prudence through a village or any thickly settled neighborhood, shall run them with great rapidity and without signals, by means whereof persons passing along the streets and themselves observing ordinary caution are struck by the train and injured, such persons may have redress in a like action. The chief qualification of this doctrine is that the party complaining of the injury must not himself have contributed to it by his own wrongful or wilful act, or by his own want of ordinary care; for if both parties were in fault, the common law will not attempt to apportion the culpability, but will leave each party where his own unwarrantable conduct or neglect has left him.

In this regard the rule of the common law is different from that which prevails in admiralty in some cases, where the consequences of the concurring fault of two parties may be apportioned between them as near as shall be found practicable. The concurring fault or negligence, however, which at law will bar an action for redress, must be such as has contributed proximately to the injury. Thus, if one drives across a railroad track without looking to the right or left, and is struck by a passing engine, he can have no redress, because he failed of ordinary prudence in not looking to see whether a train was near; but if, observing due care and prudence at that time, he is nevertheless injured, it will be no defence to the railway company that some want of proper caution may remotely have contributed to the accident. The rule of contributory negligence imputes to one who is under natural or legal guardianship the negligence of the guardian; so that a child run over in the street may not recover damages from the party accidentally running over him, if the parent who had charge of him was careless in permitting him thus to wander into a place of danger; and an insane person may not recover where the trustee negligently suffers him to be abroad.

And this rule is applicable where one temporarily places himself in the hands or under the control of another; as where one takes a seat in the carriage of another and is carelessly driven by the latter into danger, the negligence of the driver will preclude recovery for accidental injuries. Corporations as well as natural persons are liable for negligence, and municipal corporations as well as others, with this restriction, that an exercise of their legislative authority is not imputable as negligence. But if the corporation order the construction of a public work, and the execution of the work is careless and imperfect, and injury results, an action Mill lie, provided it is constructed by the corporation itself through its own agents; but if the construction is let to an independent contractor, he alone can be looked to for redress for his negligence. Public officers are in general liable for their negligence, not only to parties on whose behalf they assume to perform a duty, but also to third persons injured by their action; but from this must be excepted the chief executive of the nation or state, any officers while acting in a legislative capacity, and judicial officers and others exercising a discretionary authority, and where the negligence is predicated of their discretionary acts.

The owner of a vicious beast, knowing him to be such, is guilty of negligence if he suffers him to be at large without a keeper; but as his liability at the common law depends upon his knowledge of the vicious nature of the animal, which is not always easy of proof when it exists, it has been thought proper in some cases, especially as regards dogs, to pass statutes dispensing with this proof, and making the owner liable upon proof of the injury alone. - Where negligence results in the death of a human being, the common law gives no remedy; but this has been found a great hardship, which was remedied in England by statute in 1846, and the substance of this statute has been re-enacted in the several states of the Union, the remedy being given to or for the benefit of the parent, husband, wife, child, or estate of the person killed. The killing of a person by wilful neglect or gross carelessness may be a felonious homicide; as where a mechanic throws rubbish from a roof into the streets of a village where people are constantly passing, without looking to see if at the time it is clear; or where the engineer on a railway train drives it furiously through a town without sounding signals, or occupies the track in the time of an approaching train without taking steps to ascertain whether he may do so with safety.

If in any of those cases death results from' the negligence, the reckless and wanton conduct will stand for criminal intent; and in any case of a clear duty imposed by law, if death result from a neglect of the duty, it will be accounted criminal homicide. (See Homicide, and Manslaughter.) - The legal aspects of negligence have recently been fully considered in the valuable treatises of Shearman and Redfield (New York), and Francis Wharton (Philadelphia).