458 HARVARD LAW REVIEW. ligence is charged the test is what duty there was on the part of the person charged towards the special person complaining, and what was its extent at the time and under the particular circumstances. The duty imposed upon a man to exercise care towards another must vary according to the character of the danger, whether hid- den or obvious, great or small, and according to the relation be- tween the two men.^ The same act may be negligent as against one man, and not as against another. In a given suit, therefore, for negligence, the defendant's duty to the plaintiff at the particu- lar time of the injury is the sole thing to be considered, and not his general duty to others.^ The plaintiff in an action of tort for negligence must allege and prove a duty on the part of the defendant towards him, and a fail- ure to perform. This proves the negligence. To show that it was actionable, he must go farther, and show that this failure was the proximate cause of the injury. The defendant in such action has two distinct defences: — I. To deny that his act caused the damage at all, although ad- mitting the duty, {a) because of an intervening act of some one, or an intervening effect of something, breaking the causal connec- tion between the defendant's act and the injury; (<^) because of some act of the plaintiff's himself occurring simultaneously or sub- sequently to the defendant's act, breaking the causal connection and rendering the defendant's act no longer the sole proximate cause of the injury. II. To admit that his act caused the damage, but to deny the duty, («) because no duty was imposed by law upon persons stand- ing in the relative positions of the parties, — as, for instance, where the plaintiff is a trespasser, or, where he is not such a person as the defendant was bound to anticipate would be likely to incur the danger; (^F) because the plaintiff himself had voluntarily placed himself in such a position that no duty arose as towards him. Now, these two defences are entirely distinct, the first admitting the negligence and denying the proximate cause, the second deny- ing absolutely the negligence, i. e. the breach of duty towards the particular plaintiff. The first is a defence to the action ; the sec- ond is really proof of no basis to a right of action. The first of these defences (I. b) is that usually called contribu- 1 Cf. Lord Bowen in Thomas z'. Quartermaiiie, i8 Q. B. D. (iJ 2 Fitzgerald v. Conn. River R. R., 155 Mass. 156 (1891).
