When the preservation of an individual is inconsistent with the safety of a multitude, nothing can be more just than that the many should be preferred to the one.
 Adam Smith, The Theory of Moral Sentiments (1759). copy citation

Context

“A centinel, for example, who falls asleep upon his watch, suffers death by the laws of war, because such carelessness might endanger the whole army.13 This severity may, upon many occasions, appear necessary, and, for that reason, just and proper. When the preservation of an individual is inconsistent with the safety of a multitude, nothing can be more just than that the many should be preferred to the one. Yet this punishment, how necessary soever, always appears to be excessively severe. The natural atrocity of the crime seems to be so little, and the punishment so great, that it is with great difficulty that our heart can reconcile itself to it.” source