RegEx'es can be likened to Mathematical Set Theory. They can help us group vague unknown data which needs to be processed in some way. And just like someone can

RegEx'es can be likened to Mathematical Set Theory. They can help us group vague unknown data which needs to be processed in some way. And just like someone can get carried away with the over normalisation of a database, the same can happen with complex RegEx's where the time and complexity could be reduced if a single complex RegEx became part of a decision tree like code process using other RegEx's. Mathematical Naïve Set Theory is fundamentally flawed, otherwise Russell's Paradox wouldn't exist.