In 1949 an operation was performed using anaesthetic kept in a vessel with tiny cracks that had allowed disinfectant to perforate the anaesthetic. The disinfectant paralysed the bones into which it was injected. Ps sued D for being paralysed. CA rejected the claim, saying that, given the level of medical knowledge in 1949, the hospital could not have been expected to consider the risk of the vessel cracking or to take precautions to detect if there had been cracking.
Lord Denning: We should avoid overly-using hindsight to impose unrealistic standards. If it could not reasonably be foreseen that one’s conduct would harm P, then one has no duty of care to him (Bourhill v Young). Here there was no reasonable foreseeability. Apart from duty, causation has to be proved and remoteness taken into account. We should generally ask, as a substitute for all 3, “is the consequence within the risk” and apply it using common sense. This is FAR too vague and won’t answer the questions that foreseeability, causation and remoteness are addressing with greater precision.