Experiment Is Fundamentally Only Induced Observation.

Man Does Not Limit Himself To Seeing; He Thinks And Insists On Learning The Meaning Of Phenomena Whose Existence Has Been Revealed To Him By Observation. So He Reasons, Compares Facts, Puts Questions To Them, And By The Answers Which He Extracts, Tests One By Another. This Sort Of Control, By Means Of Reasoning And Facts, Is What Constitutes Experiment, Properly Speaking; And It Is The Only Process That We Have For Teaching Ourselves About The Nature Of Things Outside Us.

We Must Keep Our Freedom Of Mind, ... And Must Believe That In Nature What Is Absurd, According To Our Theories, Is Not Always Impossible.

Real Science Exists, Then, Only From The Moment When A Phenomenon Is Accurately Defined As To Its Nature And Rigorously Determined In Relation To Its Material Conditions, That Is, When Its Law Is Known. Before That, We Have Only Groping And Empiricism.

The True Worth Of An Experimenter Consists In His Pursuing Not Only What He Seeks In His Experiment, But Also What He Did Not Seek.

Men Who Have Excessive Faith In Their Theories ... Make Poor Observations, Because They Choose Among The Results Of Their Experiments Only What Suits Their Object, Neglecting Whatever Is Unrelated To It And Carefully Setting Aside Everything Which Might Tend Toward The Idea They Wish To Combat