What is the test for determining whether there is a causal connection between a breach of duty and damage?

In Athey v. Leonati, 1996 CanLII 183 (SCC), [1996] 3 S.C.R. 458, while not a case dealing with occupiers' liability, does cover the principles to be considered in determining whether there is a causal connection between a breach of duty and damage. At p. 466, Major J. stated: ¶13 Causation is established where the plaintiff proves to the civil standard on a balance of probabilities that the defendant caused or contributed to the injury ... ¶14 The general, but not conclusive, test for causation is the "but for" test, which requires the plaintiff to show that the injury would not have occurred but for the negligence of the defendant ... ¶15 The "but for" test is unworkable in some circumstances, so the courts have recognized that causation is established where the defendant's negligence "materially contributed" to the occurrence of the injury ...