an “early modern scientific movement”—chronologically, a “Long Sixteenth Century” that began with the late-fifteenth century conflict about the status of astrological prognostication and ended in the early seventeenth century when the Catholic Church extended its skepticism (and its enforcement machinery) about naturalistic foreknowledge to the reality of the heliocentric planetary ordering. Rather than revolutionary, paradigmatic rupture, this periodization offers a picture of gradual, multi-generational change that broadly conjoins a backward-looking veneration for ancient tradition with a forward-looking, modernizing valuation of change and novelty. 12. Kepler’ Epitome of Copernican Astronomy (1618–21) and Galileo’s Dialogue Concerning the Two Chief World Systems (1632) consolidated a critical mass of novel physical claims and arguments developed between the 1580s and the telescopic discoveries of 1610-13. While Kepler and Galileo disagreed on some important issues (Galileo, for example, never accepted Kepler’s elliptical orbits), together their presentations made possible a multifaceted, robust public debate (1620s-40s) that a new generation of modernizing natural philosophers—including René Descartes (1596-1650), Pierre Gassendi (1592-1655), Marin Mersenne (1588-1648), and Thomas Hobbes (1588-1679)—selectively incorporated into their own original arguments with tradition-bound natural philosophers in the universities. In this period, the Copernican Question became a struggle that overtly involved natural philosophy, a battle framed as one between competing “world systems”. 13. By 1651, the Jesuit astronomer Giovanni Battista Riccioli (1598-1651), writing in the shadow of Galileo’s Trial in 1633, produced a massive work (Almagestum novum) in which he assembled 49 arguments in favor of the daily and annual motions of the Earth as against 77 arguments contrary to the Earth’s motions. While presenting the decision between the two as a contrasting of probable arguments, in the end, he decisively eliminated any uncertainty by appeal to “both sacred authority and Divine Scriptures.” 14. Although the midcentury modernizers were all followers of Copernicus’s system, like the late-sixteenth defenders of Copernicus, they continued to be disunified in the kinds of principles and arguments to which they appealed. For example, a proposal that side-stepped the difficult technical arguments grounding Kepler’s ellipses and Galileo’s falling bodies and which helped to popularize support with new audiences was the argument for a plurality of worlds. Building on Giordano Bruno’s claim that God must have used his omnipotence to create an infinite universe with innumerable worlds and Galileo’s telescopic discovery of a moon with Earthlike characteristics, John Wilkins argued that an infinite, omnipotent god must have used his power to create other living