There Are Cats And Cats.

A Thing Is Not Proved Just Because No One Has Ever Questioned It. What Has Never Been Gone Into Impartially Has Never Been Properly Gone Into. Hence Scepticism Is The First Step Toward Truth. It Must Be Applied Generally, Because It Is The Touchstone.

There Is Less Harm To Be Suffered In Being Mad Among Madmen Than In Being Sane All By Oneself.

From Fanaticism To Barbarism Is Only One Step.

In Order To Get As Much Fame As One's Father One Has To Much More Able Than He.

All Things Must Be Examined, Debated, Investigated Without Exception And Without Regard For Anyone's Feelings... We Must Run Roughshod Over All These Ancient Puerilities, Overturn The Barriers That Reason Never Erected, Give Back To The Arts And Sciences The Liberty That Is So Precious To Them.