The value of human life
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Proposition A human life is worth the amount that would be given for the use of his power.
The value or worth of a man is, as of all other things, his price; that is to say, so much as would be given for the use of his power, and therefore is not absolute, but a thing dependent on the need and judgement of another. An able conductor of soldiers is of great price in time of war present or imminent, but in peace not so. A learned and uncorrupt judge is much worth in time of peace, but not so much in war. And as in other things, so in men, not the seller, but the buyer determines the price. For let a man, as most men do, rate themselves at the highest value they can, yet their true value is no more than it is esteemed by others.
Hobbes, Lev X 16