What is the “real” reality? Is buying a pet expensive food the right thing to do or a waste of money? According to sociologist W. I. Thomas , “if a person perceives a situation as real, it is real in its consequences.” This statement is also known as the Thomas Theorem. In other words, our behavior depends not on the objective reality of a situation but on our subjective interpretation of reality. The consequences and results of behavior make it real. For example, a teenager who is defined as deviant might begin to act deviant. He makes his label real.
In his 1562 narrative poem The Tragical History of Romeus and Juliet , Arthur Brooke translated Boaistuau faithfully but adjusted it to reflect parts of Chaucer's Troilus and Criseyde .  There was a trend among writers and playwrights to publish works based on Italian novelles —Italian tales were very popular among theatre-goers—and Shakespeare may well have been familiar with William Painter 's 1567 collection of Italian tales titled Palace of Pleasure .  This collection included a version in prose of the Romeo and Juliet story named "The goodly History of the true and constant love of Romeo and Juliett" . Shakespeare took advantage of this popularity: The Merchant of Venice , Much Ado About Nothing , All's Well That Ends Well , Measure for Measure , and Romeo and Juliet are all from Italian novelle . Romeo and Juliet is a dramatisation of Brooke's translation, and Shakespeare follows the poem closely but adds extra detail to both major and minor characters (in particular the Nurse and Mercutio).