Voltaire's Philosophical Dictionary · Voltaire
PREJUDICES OF THE SENSES
Is it not strange that our eyes always deceive us, even when we have very good sight, and that on the contrary our ears do not deceive us? Let your well-informed ear hear "You are beautiful, I love you"; it is quite certain that someone has not said "I hate you, you are ugly": but you see a smooth mirror; it is demonstrated that you are mistaken, it has a very uneven surface. You see the sun as about two feet in diameter; it is demonstrated that it is a million times bigger than the earth. It seems that God has put truth in your ears, and error in your eyes; but study optics, and you will see that God has not deceived you, and that it is impossible for objects to appear to you otherwise than you see them in the present state of things. The sun rises, the moon also, the earth is motionless: these are natural physical prejudices. But that lobsters are good for the blood, because when cooked they are red; that eels cure paralysis because they wriggle; that the moon affects our maladies because one day someone observed that a sick man had an increase of fever during the waning of the moon; these ideas and a thousand others are the errors of ancient charlatans who judged without reasoning, and who, being deceived, deceived others.
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