I Do Not Know What To Say

I Would Beg The Wise And Learned Fathers (of The Church) To Consider With All Diligence The Difference Which Exists Between Matters Of Mere Opinion And Matters Of Demonstration. ... [i]t Is Not In The Power Of Professors Of The Demonstrative Sciences To Alter Their Opinions At Will, So As To Be Now Of One Way Of Thinking And Now Of Another. ... [d]emonstrated Conclusions About Things In Nature Of The Heavens, Do Not Admit Of Being Altered With The Same Ease As Opinions To What Is Permissible Or Not, Under A Contract, Mortgage, Or Bill Of Exchange.

That Sculpture Is More Admirable Than Painting For The Reason That It Contains Relief And Painting Does Not Is Completely False. ... Rather, How Much More Admirable The Painting Must Be Considered, If Having No Relief At All, It Appears To Have As Much As Sculpture!

Measure What Can Be Measured, And Make Measureable What Cannot Be Measured.

But, Because My Private Lectures And Domestic Pupils Are A Great Hinderance And Intteruption Of My Studies, I Wish To Live Entirely Exempt From The Former, And In Great Measure From The Latter. ... In Short, I Should Wish To Gain My Bread From My Writings.

Surely It Is A Great Thing To Increase The Numerous Host Of Fixed Stars Previously Visible To The Unaided Vision, Adding Countless More Which Have Never Before Been Seen, Exposing These Plainly To The Eye In Numbers Ten Times Exceeding The Old And Familiar Stars.