I Think; Therefore I Am.

The Principal Use Of Prudence, Of Self-control, Is That It Teaches Us To Be Masters Of Our Passions, And To So Control And Guide Them That The Evils Which They Cause Are Quite Bearable, And That We Even Derive Joy From Them All.

If ... It Is Not In My Power To Arrive At The Knowledge Of Any Truth, I May At Least Do What Is In My Power, Namely, Suspend Judgement.

If I Found Any New Truths In The Sciences, I Can Say That They Follow From, Or Depend On, Five Or Six Principal Problems Which I Succeeded In Solving And Which I Regard As So Many Battles Where The Fortunes Of War Were On My Side.

The Greatest Minds, As They Are Capable Of The Highest Excellencies, Are Open Likewise To The Greatest Aberrations; And Those Who Travel Very Slowly May Yet Make Far Greater Progress, Provided They Keep Always To The Straight Road, Than Those Who, While They Run, Forsake It.

On The One Hand I Have A Clear And Distinct Idea Of Myself, In So Far As I Am A Thinking, Non-extended Thing; And On The Other Hand I Have A Distinct Idea Of Body, In So Far A This Is Simply An Extended, Non-thinking Thing. And, Accordingly, It Is Certain That I Am Really Distinct From My Body, And Exist Without It.