Gutenberg Bible makes literature more accessible, which empowers citizens to develop their own powers of critical thinking and challenge the power of other doctrines such as religion. This new critical thinking makes all cities immune to foreign <l:6,29>conversion<e> attacks and boosts the Civilization's <l:6,97>science<e> by 10%; it also <l:6,24>reforms all of your cities<e> back to your own faith.