an end for the future distinguishes punishment from revenge, and punishment only has this end when it is inflicted in fulfillment of a law. it thus announces itself as inevitable in every future case, and thus the law obtains the power to deter, in which its end really consists. now here a kantian would inevitably reply that certainly according to this view the punished criminal would be used merely as a means. this proposition, so unweariedly repeated by all the kantians, man must always be treated as an end, never as a means, certainly sounds significant, and is therefore a very suitable proposition for those who like to have a formula which saves them all further thought; but looked at in the light, it is an exceedingly vague, indefinite assertion, which reaches its aim quite indirectly, requires to be explained, defined, and modified in every case of its application, and, if taken generally, is insufficient, meager, and moreover problematical.   the murderer who has been condemned to the punishment of death according to law must now, at any rate, and with complete right, be used as a mere means. for public security, the chief end of the state, is disturbed by him; indeed it is abolished if the law is not carried out. the murderer, his life, his person, must now be the means of fulfilling the law, and thereby of re-establishing the public security. and he is made such a means with perfect right, in fulfillment of the contract of the state, which was entered into by him because he was a citizen, and in accordance with which, in order to enjoy security for his life, freedom, and property, he has pledged his life, his freedom, and his property for the security of all, which pledge has now been forfeited.
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