This is right on target so I’ll just let it speak for itself. 

The_combinations_rule Stan’s right: this is the number one rule for any creative venture, including some of the best teaching that I ever received (and that I’ve seen practiced through the profession’s lens). The best teachers always seemed to know a lot about stuff that had nothing to do with the ‘subject’ in hand. They always knew the names of plants, birds, trees, obscure books and films.

edublogs: The Combinations Rule: underlines creative thought