Every Blockhead Is Thoroughly Persuaded That He Is In the Right

Baltasar Gracián y Morales? Mountstuart Grant Duff? Joseph Jacobs? Christopher Maurer? Martin Fischer? Apocryphal? Question for Quote Investigator: Thoughtful people periodically revise their opinions as their knowledge grows. Obstinate and foolish people develop an opinion and then refuse to change it even when evidence accumulates that their original position is deeply flawed. Clinging to erroneous …