You May Force Me To Say What

But Some, Besides Allegiance To Their Original Error, Possess I Know Not What Fanciful Interest In Remaining Hostile Not So Much Toward The Things In Question As Toward Their Discoverer.

They Who Depend Upon Manifest Observations Will Philosophize Better Than Those Who Persist In Opinions Repugnant To The Senses.

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.

One Can Understand Nature Only When One Has Learned The Language And The Signs In Which It Speaks To Us; But This Language Is Mathematics And These Signs Are Methematical Figures.

I Truly Believe The Book Of Philosophy To Be That Which Stands Perpetually Open Before Our Eyes, Though Since It Is Written In Characters Different From Those Of Our Alphabet It Cannot Be Read By Everyone.