based on piety, religion, on a knowledge of divine omnipotence and the weakness of the human understanding. It is the opinion of good authorities that the foregoing introduction was first written by Galileo, then revised by the censor at Rome—perhaps by the Pope himself—and finally returned to the author with permission to make such verbal changes as would not alter the sense of the Roman revision.
In the Dialogues the three interlocutors proceed to construct a scheme of the universe, step by step. The construction is made by Simplicius, and the system proposed by Copernicus and demonstrated by Galileo emerges triumphant. All the glory is for Copernicus and his advocate, Galileo. No credit is assigned to Kepler for his discoveries which had done away with the whole apparatus of epicycles retained by Copernicus. Kepler is not mentioned here or elsewhere with praise. Simplicius objects to some mathematical reasoning because Aristotle recommended his disciples to abstain from geometry. Salviati thinks Aristotle wise; for geometry is the art by which his errors and deceits are discovered. As to the empty spaces beyond Saturn: who are we to judge of the greatness of the universe? Can we say that these spaces are useless because we see no planet there? May they not be peopled with invisible planets? Who suspected the existence of the moons of Jupiter? Who tells us that all the heavenly bodies were created for us? Certain authors—Kepler, for one—assert that tides are caused by the moon. Galileo will not waste his time in refuting such assertions. Nothing is so astonishing to Galileo as that Kepler, a free and penetrating spirit, should have assented to such 'ineptitudes.' Simplicius on his part declares that the tides are miracles. In all the book there is no discussion of Scriptural texts.
It is not necessary to carry the analysis of these famous dialogues further. The arguments employed are so familiar to us that we forget they were once fresh and novel. They were accepted by Galileo's contemporaries as witty and brilliant, and even now Italians admire their style, though most English readers find them, as a whole, prolix, not to say dull. The Copernican doctrine is enforced in every possible way. Every argument for the Aristotelian theory is brought forward, in turn, by Simplicius only to be utterly refuted. Sarcasm is unsparingly employed. Simplicius is not only wrong, but ludicrously so. After each unusually convincing passage Salviati is careful to add that, after all, the Copernican doctrine is a 'fantasy' or a 'vain chimera.' At the termination of the dialogues, which extend over four days, no general summing-up is made. The reader is left to draw his own conclusions. Salviati apologizes to Simplicius for the ardor of his language and assures him that he had no intention to offend him, but wished rather to stimulate him to communicate his 'sublime' ideas—ideas which have been utterly refuted in the course
