Who Would Dare Assert That We Know

Philosophy [nature] Is Written In That Great Book Which Ever Is Before Our Eyes -- I Mean The Universe -- But We Cannot Understand It If We Do Not First Learn The Language And Grasp The Symbols In Which It Is Written. The Book Is Written In Mathematical Language, And The Symbols Are Triangles, Circles And Other Geometrical Figures, Without Whose Help It Is Impossible To Comprehend A Single Word Of It; Without Which One Wanders In Vain Through A Dark Labyrinth.

By Denying Scientific Principles, One May Maintain Any Paradox.

Vision, I Say, Is Related To Light Itself. But Of This Sensation And The Things Pertaining To It, I Pretend To Understand But Little; And Since Even A Long Time Would Not Suffice To Explain That Trifle, Or Even To Hint At An Explanation, I Pass Over This In Silence.

Take Note, Theologians, That In Your Desire To Make Matters Of Faith Out Of Propositions Relating To The Fixity Of Sun And Earth You Run The Risk Of Eventually Having To Condemn As Heretics Those Who Would Declare The Earth To Stand Still And The Sun To Change Position-eventually, I Say, At Such A Time As It Might Be Physically Or Logically Proved That The Earth Moves And The Sun Stands Still.

The Deeper I Go In Considering The Vanities Of Popular Reasoning, The Lighter And More Foolish I Find Them. What Greater Stupidity Can Be Imagined Than That Of Calling Jewels, Silver, And Gold "precious," And Earth And Soil "base"?