In Order To Improve The Mind, We

I Am Thinking, Therefore I Exist. (...) I Was A Substance Whose Whole Essence Or Nature Is Solely To Think, And Which Does Not Require Any Place, Or Depend On Any Material Thing, In Order To Exist. Accordingly This 'i' - That Is, The Soul By Which I Am What I Am - Is Entirely Distinct From The Body, And Indeed Is Easier To Know Than The Body, And Would Not Fail To Be Whatever It Is, Even If The Body Did Not Exist.

[about Pierre De Fermat] It Cannot Be Denied That He Has Had Many Exceptional Ideas, And That He Is A Highly Intelligent Man. For My Part, However, I Have Always Been Taught To Take A Broad Overview Of Things, In Order To Be Able To Deduce From Them General Rules, Which Might Be Applicable Elsewhere.

It Is Not Enough To Have A Good Mind. The Main Thing Is To Use It Well.

The Reading Of All Good Books Is Indeed Like A Conversation With The Noblest Men Of Past Centuries Who Were The Authors Of Them, Nay A Carefully Studied Conversation, In Which They Reveal To Us None But The Best Of Their Thoughts.

Some Years Ago I Was Struck By The Large Number Of Falsehoods That I Had Accepted As True In My Childhood, And By The Highly Doubtful Nature Of The Whole Edifice That I Had Subsequently Based On Them. I Realized That It Was Necessary, Once In The Course Of My Life, To Demolish Everything Completely And Start Again Right From The Foundations If I Wanted To Establish Anything At All In The Sciences That Was Stable And Likely To Last.