  A number of criticisms question whether this account captures what is normally going on in analogical reasoning. One criticism focuses on the fact that the principle must track the existing cases and try to make the best of them. Unless the decisions are all correct on the merits, any principle based on them must itself be flawed: for if it were morally correct it would not support the mistaken decisions. The question this raises is whether it can be justifiable to use such a principle to decide a novel case, rather than decide the case on its own merits. Can there be ‘principles’ of this kind, which are neither conventional parts of a practice nor morally correct? (see further Alexander 1996b, 1998, Alexander and Kress 1995, 1997) A more common view, however, is that a principle that makes best sense of a series of cases or aspects of legal doctrine can have some justificatory force even though the cases or doctrines are morally imperfect. In the case of tort liability, for example, the cases might be best explained by the principle that liability will only arise where the defendant's conduct has been unreasonable, i.e., that both harm to the plaintiff and unreasonable conduct is necessary for liability. This principle may be morally mistaken, i.e., there may be situations where even reasonable conduct should result in legal liability. Nevertheless the principle may still be regarded as having some justificatory force in the context of that legal system. A judge might think that the correct moral principle is that other things being equal there should be no liability without unreasonable conduct. But although the law is imperfect in this way, the legal principle still has some force because it is a near enough neighbour to the correct principle and it explains the existing  cases.[19]