I want to say "So barring time travel, Person X could not possibly be of the line of Person Y." This would be the only 'cute' moment in the paper. Is that acceptable?
When you get the urge to eat chocolate, sit down and do nothing but observe your thoughts for five minutes. It should be like watching a river. If you get lost in the flow of your thoughts, gently refocus.
After that, consider your urge to eat chocolate. Most of the time you will find it...