The Chief Cause Of Human Errors Is

I Should Consider That I Know Nothing About Physics If I Were Able To Explain Only How Things Might Be, And Were Unable To Demonstrate That They Could Not Be Otherwise.

Give Me Extension And Motion And I Will Construct The Universe.

There Is A Difference Between Happiness, The Supreme Good, And The Final End Or Goal Toward Which Our Actions Ought To Tend. For Happiness Is Not The Supreme Good, But Presupposes It, Being The Contentment Or Satisfaction Of The Mind Which Results From Possessing It.

By 'god', I Understand, A Substance Which Is Infinite, Independent, Supremely Intelligent, Supremely Powerful, And Which Created Both Myself And Everything Else [...] That Exists. All These Attributes Are Such That, The More Carefully I Concentrate On Them, The Less Possible It Seems That They Could Have Originated From Me Alone. So, From What Has Been Said It Must Be Concluded That God Necessarily Exists.

But I Cannot Forget That, At Other Times I Have Been Deceived In Sleep By Similar Illusions; And, Attentively Considering Those Cases, I Perceive So Clearly That There Exist No Certain Marks By Which The State Of Waking Can Ever Be Distinguished From Sleep, That I Feel Greatly Astonished; And In Amazement I Almost Persuade Myself That I Am Now Dreaming.