value judgments and the infusion of policy considerations. In Rutherford v Owens-Illinois Inc 67 Cal. Rptr. 2d 16 (1997), in a judgment with which the Chief Justice and all save one member of the Supreme Court of California concurred, Baxter J observed (at p 19):

 Proof of causation in such cases will always present inherent practical difficulties, given the long latency period of asbestos-related disease, and the occupational settings that commonly exposed the worker to multiple forms and brands of asbestos products with varying degrees of toxicity. In general, however, no insuperable barriers prevent an asbestos-related cancer plaintiff from demonstrating that exposure to the defendant's asbestos products was, in reasonable medical probability, a substantial factor in causing or contributing to his risk of developing cancer. We conclude that plaintiffs are required to prove no more than this. In particular, they need not prove with medical exactitude that fibers from a particular defendant's asbestos-containing products were those, or among those, that actually began the cellular process of malignancy. McLachlin J, extra-judicially ("Negligence Law - Proving the Connection", in Torts Tomorrow, A Tribute to John Fleming, ed Mullany and Linden, LBC Information Services 1998, at p 16), has voiced a similar concern: Tort law is about compensating those who are wrongfully injured. But even more fundamentally, it is about recognising and righting wrongful conduct by one person or a group of persons that harms others. If tort law becomes incapable of recognising important wrongs, and hence incapable of righting them, victims will be left with a sense of grievance and the public will be left with a feeling that justice is not what it should be. Some perceive that this may be occurring due to our rules of causation.

In recent years, a conflation of factors have caused lawyers, scholars and courts to question anew whether the way tort law has traditionally defined the necessary relationship between tortious acts and injuries is the right way to define it, or at least the only way. This questioning has happened in the United States and in England and has surfaced in Australia. And it is happening in Canada. Why is this happening? Why are courts now asking questions that for decades, indeed centuries, did not pose themselves, or if they did, were of no great urgency? I would suggest that it is because too often the traditional 'but-for', all-or-nothing, test denies recovery where our instinctive sense of justice - of what is the right result for the situation - tells us the victim should obtain some compensation. Professor Christian von Bar (The Common European Law of Torts, 2000, vol 2, pp 441-443) has written: German law on medical negligence provides the example of the reduced burden of proof of causation in cases of grave treatment errors. Recent environmental legislation has reacted to the problem of scientifically 37