Here we are to remember that in consequence of our opinion that labor is the Father and active principle of wealth, as lands are the Mother, that the state by killing, mutilating, or imprisoning their members do withal punish themselves.
William PettyThe method I take to do this is not yet very usual; for instead of using only comparative and superlative Words, and intellectual Arguments, I have taken the course (as a Specimen of the Political Arithmetic I have long aimed at) to express myself in Terms of Number, Weight, or Measure; to use only Arguments of Sense, and to consider only such Causes, as have visible Foundations in Nature.
William PettyWithout the knowledge of the true number of the people, as a principle, the whole scope and use of keeping bills of birth and burials is impaired; wherefore by laborious conjectures and calculations to deduce the number of people from the births and burials, may be ingenious, but very preposterous.
William Petty