It is a basic principle of tort law that the plaintiff must be placed in the position he or she would have been in if not for the defendant’s negligence, no better or worse. The tortfeasor must take his or her victim as they find them, even if the plaintiff’s injuries are more severe than they would be for a normal person (the thin skull rule). However, the defendant need not compensate the plaintiff for any debilitating effects of a pre-existing condition which the plaintiff would have experienced anyway (the crumbling skull rule): Athey v. Leonati, 1996 CanLII 183 (SCC),  3 S.C.R. 458 at paras. 32-35.
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