 Interest in the Galileo affair was revived in the early 19th century , when Protestant polemicists used it ( and other events such as the Spanish Inquisition and the Flat Earth Myth ) to attack Roman Catholicism . Interest in it has waxed and waned ever since . In 1939 Pope Pius XII , in his first speech to the Pontifical Academy of Sciences , within a few months of his election to the papacy , described Galileo as being among the " most audacious heroes of research ... not afraid of the stumbling blocks and the risks on the way , nor fearful of the funereal monuments " . His close advisor of 40 years , Professor Robert Leiber , wrote : " Pius XII was very careful not to close any doors ( to science ) prematurely . He was energetic on this point and regretted that in the case of Galileo . " 
