Early Glimpses of Bias

"Nothing is easier than self-deceit. For what each man wishes, that he also believes to be true" (Demosthenes, "Olynthiac", 349 BC)

“Men willingly believe what they wish to be true.” (Julius Caesar, “De Bello Gallico”, Book III, 58–49 BC)

“You can have no greater or lesser dominion than the one over yourself. The greatest deception men suffer is from their own opinions.” (Leonardo da Vinci)

“Man prefers to believe what he prefers to be true.” (Francis Bacon, “Novum Organum”, 1620)

“The human brain is a complex organ with the wonderful power of enabling man to find reasons for continuing to believe whatever it is that he wants to believe.” (Voltaire)

“Men judge things according to the disposition of their minds, and had rather imagine things than understand them.” (Baruch Spinoza, “Ethics”, Book I, 1677)

“Reasoning will never make a Man correct an ill Opinion, which by Reasoning he never acquired.” ( Jonathan Swift, “A Letter to a Young Gentleman, Lately Enter’d Into Holy Orders by a Person of Quality”, 1721)

“It is hard to prevent oneself from believing what one so keenly desires, and who can doubt that the interest we have in admitting or denying the reality of the Judgement to come determines the faith of most men in accordance with their hopes and fears.” (Jean-Jacques Rousseau, “Reveries of the Solitary Walker”, 1782)

“Men are not to be reasoned out of an opinion that they have not reasoned themselves into.” (Fisher Ames, 1786)

“How little ground there can be to hope that men may be reasoned out of their errors, when in fact they were never reasoned into them." (Lyman Beecher, 1823)