In Science, The Best Precept Is To

Put Off Your Imagination, As You Put Off Your Overcoat, When You Enter The Laboratory. Put It On Again, As You Put On Your Overcoat, When You Leave.

We Must Alter Theory To Adapt It To Nature, But Not Nature To Adapt It To Theory.‎

Now, A Living Organism Is Nothing But A Wonderful Machine Endowed With The Most Marvellous Properties And Set Going By Means Of The Most Complex And Delicate Mechanism.

To Be Worthy Of The Name, An Experimenter Must Be At Once Theorist And Practitioner. While He Must Completely Master The Art Of Establishing Experimental Facts, Which Are The Materials Of Science, He Must Also Clearly Understand The Scientific Principles Which Guide His Reasoning Through The Varied Experimental Study Of Natural Phenomena. We Cannot Separate These Two Things: Head And Hand. An Able Hand, Without A Head To Direct It, Is A Blind Tool; The Head Is Powerless Without Its Executive Hand.

I Do Not ... Reject The Use Of Statistics In Medicine, But I Condemn Not Trying To Get Beyond Them And Believing In Statistics As The Foundation Of Medical Science. ... Statistics ... Apply Only To Cases In Which The Cause Of The Facts Observed Is Still [uncertain Or] Indeterminate. ... There Will Always Be Some Indeterminism ... In All The Sciences, And More In Medicine Than In Any Other. But Man's Intellectual Conquest Consists In Lessening And Driving Back Indeterminism In Proportion As He Gains Ground For Determinism By The Help Of The Experimental Method.