46o HARVARD LAW REVIEW. the plaintiff to prove due care on his part, because evidence of a want of due care goes directly to disprove one essential of the plain- tiff's case, i. e. the proximate causality of the defendant's act. That the two defences above stated are dissimilar and distinct^ will be seen on examination. Due care is taking the precautions which an ordinary reasonable, prudent man would take under the circumstances. Now, there are many undertakings attended with more or less peril which such a man in the exercise of prudence may enter upon, and does enter upon, every day. In such a case the defendant cannot say, " You are guilty of want of care in expos- ing yourself to the danger. You are guilty of contributory negli- gence." There is no negligence in the entering upon the act, it being an act often undertaken, though dangerous, by reasonable and prudent men. What the defendant can say is, however, " You may have been as careful as the most careful man ; you may have done a thing that many prudent men do, but you have exposed yourself, with full knowledge and of your own accord, to a danger which I have brought about. You have hence shown that you agree to take your chances of the danger. I admit that this was not careless of you. But you did assume the risk. I therefore had no duty^ towards you, and you have no action against me." Furthermore, a man, having entered upon a dangerous undertaking with eyes fully open to the danger, may use all the care in the world.^ In fact, the very danger may make him even more than usually careful. In such a case contributory negligence cannot be predicated of him. The question is a larger one. " Has he volun- tarily assumed the risk of the danger?" As Wharton says,* " Negligence necessarily excludes a condition of mind which is capable either of designing an injury to another or agreeing that an injury should be received from another. To contributory negli- gence, therefore, the maxim Volenti no7t fit injuria, does not apply, because a negligent person exercises no will at all!' ^ It is evi- 1 Importance of distinction is pointed out in Erie's summing up to the jury in Indermaur v. Dames, L. R. i C. P. p. 277. 2 Some judges, like Esher, M. R., in Yarmouth v. France, 19 Q. B. D. p. 653 (1887), prefer not to say that the defendant owed the plaintiff no duty, but that " though he owed him a duty, the breach of this duty gives no right of action, that it is what is called a duty of imperfect obligation." This would seem to be a mere juggling with words. «
- Mimer v. Conn. River R. R., 153 Mass. 402 (1891).
- Wharton on Negligence, § 132.
^ How badly confused the two defences may be can be seen from this extract from an otherwise admirable opinion on the subject : " It may be said that the voluntary
