The first is that of Austin, which is essentially the theory of a criminalist. According to him, the characteristic [82] feature of law, properly so called, is a sanction or detriment threatened and imposed by the sovereign for disobedience to the sovereign's commands. As the greater part of the law only makes a man civilly answerable for breaking it, Austin is compelled to regard the liability to an action as a sanction, or, in other words, as a penalty for disobedience. It follows from this, according to the prevailing views of penal law, that such liability ought only to be based upon personal fault; and Austin accepts that conclusion, with its corollaries, one of which is that negligence means a state of the party's mind. /1/ These doctrines will be referred to later, so far as necessary. The other theory is directly opposed to the foregoing. It seems to be adopted by some of the greatest common law authorities, and requires serious discussion before it can be set aside in favor of any third opinion which may be maintained. According to this view, broadly stated, under the common law a man acts at his peril. It may be held as a sort of set-off, that he is never liable for omissions except in consequence of some duty voluntarily undertaken. But the whole and sufficient ground for such liabilities as he does incur outside the last class is supposed to be that he has voluntarily acted, and that damage has ensued. If the act was voluntary, it is totally immaterial that the detriment which followed from it was neither intended nor due to the negligence of the actor. In order to do justice to this way of looking at the subject, we must remember that the abolition of the common-law forms of pleading has not changed the rules of substantive law. Hence, although pleaders now generally [83] allege intent or negligence, anything which would formerly have been sufficient to charge a defendant in trespass is still sufficient, notwithstanding the fact that the ancient form of action and declaration has disappeared. In the first place, it is said, consider generally the protection given by the law to property, both within and outside the limits of the last-named action. If a man crosses his neighbor's boundary by however innocent a mistake, or if his cattle escape into his neighbor's field, he is said to be liable in trespass quare clausum fregit. If an auctioneer in the most perfect good faith, and in the regular course of his business, sells goods sent to his rooms for the purpose of being sold, he may be compelled to pay their full value if a third person turns out to be the owner, although he has paid over the proceeds, and has no means of obtaining indemnity.