The syllabus of errors demonstrates Pius obsession with being right and arrogant. Pius was an ego maniac and a theological dictator. He was so bitter and full of self importance that he invented Papal Infallibility which basically means when he speaks about faith and morals its impossible to be wrong. Clearly demonstrating that when you become pope you become God. He hated the modern world and wanted to bring Catholicism right back to the council of Trent. One of the worst popes in history.