Page:Hull 1900 Petty's Place in the History of Economic Theory.djvu/7

Rh  there. He procured from Romsey some important figures for Graunt's use; and he may have revised or even have written the "Conclusion" of the Observations and their curious dedicatory epistle addressed to Sir Robert Murray, president of the Royal Society. But the chief credit of the Observations he must yield to his friend Graunt. Assuming, then, that the London Observations were written by Graunt, we may note that a fifth edition, issued in 1676, three years after his death, was prepared for the press by Petty. Petty was thus reminded of his own investigations of the Dublin bills, made shortly after the first publication of Graunt's book, and upon them and the later bills of London and Paris he soon based the eleven Essays in Political Arithmetick which form the third group of his writings. They are all descended, in this way, from Graunt's Observations; and at the beginning of the first of them Petty himself acknowledges their paternity. "The Observations upon the London Bills of Mortality," he says, "have been a new Light to the World; and the like Observation upon those of Dublin may serve as Snuffers to make the same Candle burn clearer."

  The claim of Petty's writings to economic recognition rests upon a twofold basis: first, upon their method; second, upon their content. The method is named first, not because it is more important than the content, but because, being a statistical method, and as such inapplicable to many subjects, it restricts to some extent the 