Ptolomey and Copernicus were they that have had the honour to see farthest into, and discourse most profoundly of the Worlds Systeme. About the Works of which famous Men these Dialous being chiefly conversant, I conceived it my duty to Dedicate them only to Your Highness. For laying all the weight upon these two, whom I hold to be the Ablest Wits that have left us their Works upon these Subjects; to avoid a Solecisme in Manners, I was obliged to address them to Him, who with me, is the Greatest of all Men, from whom they can receive either Glory or Patrociny. And if these two persons have so farre illuminated my Understanding as that this my Book may in a great part be confessed to belong to them, well may it also be acknowledged to belong to Your Highness, unto whose Bounteous Magnificence I owe the time and leasure I had to write it, as also unto Your Powerful Assistance, (never weary of honouring me) the means that at length I have had to publish it. May Your Highness therefore be pleased to accept of it according to Your accustomed Goodness; and if any thing shall be found therein, that may be subservient towards the information or satisfaction of those that are Lovers of Truth; let them acknowledge it to be due to Your Self, who are so expert in doing good, that Your Happy Dominion cannot shew the man that is concerned in any of those general Calamities that disturb the World; so that Praying for Your Prosperity, and continuance in this Your Pious and Laudable Custome, I humbly kiss Your Hands;
Your Most Serene Highnesses
Most Humble and most devoted
Servant and Subject
GALILEO GALILEI.
