Mathematics Is Written For Mathematicians.

Therefore, In The Course Of The Work I Have Followed This Plan: I Describe In The First Book All The Positions Of The Orbits Together With The Movements Which I Ascribe To The Earth, In Order That This Book Might Contain, As It Were, The General Scheme Of The Universe.

In So Many And Such Important Ways, Then, Do The Planets Bear Witness To The Earth's Mobility.

In The Center Of All Rests The Sun. For Who Would Place This Lamp Of A Very Beautiful Temple In Another Or Better Place That This Wherefrom It Can Illuminate Everything At The Same Time? As A Matter Of Fact, Not Unhappily Do Some Call It The Lantern; Others, The Mind And Still Others, The Pilot Of The World. Trismegistus Calls It A "visible God"; Sophocles' Electra, "that Which Gazes Upon All Things." And So The Sun, As If Resting On A Kingly Throne, Governs The Family Of Stars Which Wheel Around.

Finally We Shall Place The Sun Himself At The Center Of The Universe. All This Is Suggested By The System Of Procession Of Events And The Harmony Of The Whole Universe, If Only We Face The Facts, As They Say, "with Eyes Wide Open."

For When A Ship Is Floating Calmly Along, The Sailors See Its Motion Mirrored In Everything Outside, While On The Other Hand They Suppose That They Are Stationary, Together With Everything On Board. In The Same Way, The Motion Of The Earth Can Unquestionably Produce The Impression That The Entire Universe Is Rotating.