It Is... Easy To Be Certain. One

Over Against Any Cognition, There Is An Unknown But Knowable Reality; But Over Against All Possible Cognition, There Is Only The Self-contradictory. In Short, Cognizability (in Its Widest Sense) And Being Are Not Merely Metaphysically The Same, But Are Synonymous Terms.

The Idea Does Not Belong To The Soul; It Is The Soul That Belongs To The Idea.

A True Proposition Is A Proposition Belief Which Would Never Lead To Such Disappointment So Long As The Proposition Is Not Understood Otherwise Than It Was Intended.

Kepler's Discovery Would Not Have Been Possible Without The Doctrine Of Conics. Now Contemporaries Of Kepler-such Penetrating Minds As Descartes And Pascal-were Abandoning The Study Of Geometry ... Because They Said It Was So Utterly Useless. There Was The Future Of The Human Race Almost Trembling In The Balance; For Had Not The Geometry Of Conic Sections Already Been Worked Out In Large Measure, And Had Their Opinion That Only Sciences Apparently Useful Ought To Be Pursued, The Nineteenth Century Would Have Had None Of Those Characters Which Distinguish It From The Ancien Régime.

Mathematics Is Distinguished From All Other Sciences Except Only Ethics, In Standing In No Need Of Ethics.