A fallacy is the use of invalid or otherwise faulty reasoning, or "wrong moves" in the construction of an argument. A fallacious argument may be deceptive by appearing to be better than it really is.
Poetry itself is a very spiritual experience. Dante was chronicling an epic journey which historically in earlier time periods was usually formatted as a poem, such as The Odyssey technically.
A pontifex is a type of priest, and maximus is the title of someone who is 'supreme' over someone else. So, the Pontifex Maximus would be someone who is the head of all other priests.
