A utilitarian approach will result in a decision that saves the largest number of lives possible.  Every time a life is extinguished, some amount of present and future good vanishes from the world. All the good things that that person would have experienced – joy, accomplishment, delight – will no longer occur. Similarly, all the beneficially effects they will have one other people, from productively working to loving their family, will also not occur. True, people also experience unhappy times, and they sometimes negatively affect others, but in all but an exceptionally small number of cases, the net contribution of a human life to total utility is positive (indeed, if it weren’t, we probably wouldn’t consider death to be bad). Even though there will be some fluctuations in how much each life contributes to total utility – a happy doctor probably adds more utility than a miserable meter maid – it is overwhelmingly likely that saving the five lives will result in a situation of greater utility than preserving the life of the one.